Morata et al. (1993)9. Morata TC, Dunn DE, Kretshmer LK, Lemasters GK, Keith RW. Effects of occupational exposure to organic solvents and noise on hearing. Scand J Work Environ Health. 1993;19(4):245-54.
|
Noise/Toluene/Solvent mixture: |
Brazil/Cross-sectional |
190 men/random sampling/printing and paint manufacturing |
(1) 50 non-exposed |
PTA (0.5-8 kHz) |
HL/RR prevalence: |
|
- toluene (main component); |
|
|
(2) 50 exp. noise |
Immitanciometry: |
(1) 8% |
|
- xylene; |
|
|
(3) 50 exp. noise + toluene |
Decay
|
(2) 26%/4.1 (95%CI 1.4-12.2) |
|
- MEK (methyl ethyl ketone); |
|
|
(4) 39 exp. solvent mixture |
|
(3) 53%/10.9 (95%CI 4.1-28.9) |
|
- methyl isobutyl ketone. |
|
|
|
|
(4) 18%/5.0 (95%CI 1.5-7.5) |
|
|
|
|
|
|
HL classification I: majority (3) (p<0,001) |
|
|
|
|
|
|
HL classification I-IV - predictive probability (adjusted for length of service): (3)>(4)>(2)>(1) |
|
|
|
|
|
|
Recruiting (% bigger): (2) p<0,005 |
|
|
|
|
|
|
Decay (% bigger contralateral and 2 kHz): (3) p<0.001 |
Sass-Kortsak, Corey e Robertson (1995)41. Sass-Kortsak AM, Corey PN, Robertson JM. An investigation of the association and hearing loss between exposure to styrene and hearing loss. Ann Epidemiol. 1995;5(1):15-24.
|
Noise/Styrene |
Canada/Cross-sectional |
- 299 men (36.6 years ±10,7)/Convenience/Exposed: Fiber-reinforced plastic products plant Non-exposed: local offices. |
(age: 36.6±10.7 years) |
PTA (0.125-8 kHz) (beginning and end of work shift) |
HL - overall |
|
|
|
|
(1) "directly" |
|
- 10% compensation (0.5; 1; 2 and 3 kHz ≥ 25 dBNA); |
|
|
|
|
(2) "indirectly" |
|
- 1/3 PA > 25 dBNA in 6 and 8 kHz. |
|
|
|
|
(3) "non-exposed" |
|
Association between age and HL development (subjects < 50 years and HL<50 dBNA): |
|
|
|
|
Length 7.6±6.4 years |
|
- Age: significant |
|
|
|
|
|
|
- InTSty: non-significant |
|
|
|
|
|
|
- Cigarette (P=0.001 p=0.01) |
|
|
|
|
|
|
- Extra-occupational noise: signif. ((P=0.01 β= - 0.02)) |
|
|
|
|
|
|
- Extra-occupational: signif. em 4 kHz |
|
|
|
|
|
|
Correlation |
|
|
|
|
|
|
- Age and InNoise (r=0.55) - high |
|
|
|
|
|
|
- InTSty and InNoise (r=0.52) - high |
|
|
|
|
|
|
- Age and InTSty (r=0.16) - low |
|
|
|
|
|
|
Regression - InTSty/InNoise: |
|
|
|
|
|
|
- Significant association between noise and HL (3 and 4 kHz) |
|
|
|
|
|
|
- Age and InNoise: signif. interaction |
|
|
|
|
|
|
Regression - InTWA/InTWAN: |
|
|
|
|
|
|
- Association between noise and HL in 3 and 4 kHz stronger (4 kHZ - OE: P=0.006 β= 3.55) |
Morata et al. (1997a)7. Morata TC, Dunn DE, Sieber WK. Perda auditiva ocupacional a agentes ototóxicos. In: Nudelman A, Costa EA, Seligman J, Ibanez RN. Pair: perda auditiva induzida por ruído. Porto Alegre: Baggagem; 1997. p.189-201.
|
Noise/Solvent mixture: |
Brazil/Cross-sectional |
124 men/not informed/Rotogravure printing plant |
Age average: 33.8 years (21-58) |
PTA (0.5-8 kHz) |
HL (3-6kHz) - 49% (overall total) |
|
- toluene |
|
|
Study group (several combinations of solvents and noise ) |
Immitanciometry: |
HL - age and biological marker (toluene): |
|
- ethyl alcohol (ethanol) |
|
|
Average length of employment - years: |
Decay |
OR: 1.07/year of age (95%CI 1.03-1.11) |
|
- ethyl acetate |
|
|
07 (1-25) |
|
OR for 2.5 g/g of creatinine (100 ppm in the air): 4.4 (95%CI 2.50-7.45); 1.76/gram of hippuric acid (IC 95% 1.00-2.98) |
|
|
|
|
|
|
No significant interaction: between solvents, solvent mixture and noise, or individual solvent and noise. |
Morata et al. (1997b)10. Morata TC, Fiorini AC, Fischer FM, Colacioppo S, Wallingford KM, Krieg EF, et al. Toluene-induced hearing loss among rotogravure printing workers. Scand J Work Environ Health. 1997;23(4):289-98.
|
Noise/Solvent mixture: |
South America/Cross-sectional |
438 workers/Convenience/Oil refinary |
(1) 41 non-exposed |
PTA (0.5-8 kHz) |
HL (3-6kHz) bigger number (p<0.005)/OR adjusted: |
|
- benzene; |
|
|
(2) 89 (monitoring) |
Acoustic reflex |
(2) 49%/2.4 (95%CI 1.0-5.7) |
|
- toluene; |
|
|
(3) 40 (dispatch) |
Immitanciometry decay |
(3) 42%/1.8 (95%CI 0.6-4.9) |
|
- xylene; |
|
|
(4) 180 (maintenance) |
|
(4) 50%/3 (95%CI 1.3-6.9) |
|
- ethylbenzene; |
|
|
(5) 19 (sole previous exp. to aromatics) |
|
(5) 42% |
|
- cyclohexane. |
|
|
(6) 69 (quality control lab) |
|
HL (3-6 kHz): |
|
|
|
|
|
|
(6) 15% |
|
|
|
|
|
|
Reflex decay: (2) (4) (p<0.005) |
Sliwinska-Kowalska et al. (2001)30. Sliwinska-Kowalska M, Zamyslowska-Szmytke E, Szymczak W, Kotylo P, Fiszer M, et al. Hearing loss among workers exposed to moderate concentrations of solvents. Scand J Work Environ Health. 2001;27(5):335-42.
|
Noise/Solvent mixture: |
Poland/Cross-sectional |
517 workers (311 men; 206 women)/Not informed/Paint and varnish companies |
(1) 214 non-exposed (113 men, 101 women; 38.5±10.6 years) |
PTA (1-8 kHz) |
HL/RR incidence - HL in 2-8 kHz: |
|
- Mixed xylene isomers (ortho, meta and para); |
|
|
(1a) 174 |
|
(1) 36% |
|
- Ethyl acetate; |
|
|
(1b) 40 |
|
(2) 57,5% |
|
- White spirit (Detectable concentrations of toluene, butyl acetate and ethyl benzene). |
|
|
(2) 207 exp. solvents (121 men, 86 women; 39.3±9.5 years) |
|
(2a) 4.4 (95%CI 2.3-8.1) |
|
|
|
|
(2a) 104 |
|
(2b) 2.8 (95%CI 1.8-4.3) |
|
|
|
|
(2b) 103 |
|
(3) 61.5%/2.8 (95%CI 1.6-4.9) |
|
|
|
|
(3) 96 exposed noise + solvent (77 men, 19 women; 38.4±9.1 years) |
|
OR: HL risk slightly higher in (3) than (2) (all freqs.) |
|
|
|
|
Length of employment |
|
Higher hearing thresholds in 1-8 kHz: (2) (3) |
|
|
|
|
(2) 12.8±8.2 years |
|
Higher hearing thresholds averages in 2-8 kHz: (3) |
|
|
|
|
(3) 12.2±8.5 years |
|
Linear correlation: |
|
|
|
|
|
|
HL risk and solvent exposure index: not observed |
|
|
|
|
|
|
Isolated frequencies and solvent exposure index - observed (3, 4 and 6 kHz for toluene, and 2 and 3 kHz for xylene) |
Morata et al. (2002)20. Morata TC, Johnson AC, Nylen P, Svensson EB, Cheng J, et al. Audiometric findings in workers exposed to low levels of styrene and noise. J Occup Environ Med. 2002;44(9):806-14.
|
Noise/Styrene |
Sweden/Cross-sectional |
313 workers (278 men; 35 women)/Convenience/Fiberglass and metal products industry |
(1) |
PTA (0,1-8 kHz) |
PTA |
|
|
|
|
(1a) 65 exp. to styrene (43 years (21-62)) |
|
(1) > thresholds in 2, 3, 4 and 6 kHz (p<0.05), being worse than the median in 4, 6 and 8 kHz (p<0.01). |
|
|
|
|
(1b) 89 exp. to styrene and noise (43 years (21-65)) |
|
(2) thresholds worse than the median in 6 and 8 kHz (p<0.01; p<0.05) |
|
|
|
|
(2) 78 exp. to noise (42 years (20-64)) |
|
HL |
|
|
|
|
(3) 81 non-exposed (45 years (26-62)) |
|
(1a) 47% |
|
|
|
|
Length of employment - years: |
|
(1b) 48% |
|
|
|
|
(1) |
|
(2) 42% |
|
|
|
|
(1a) 17 (01−39) |
|
(3) 33% (no statistically significant difference between the groups) |
|
|
|
|
(1b) 15 (02−37) |
|
2-6kHz thresholds: |
|
|
|
|
(2) 12 (01−35) |
|
Worse for (1) compared to (2) and (3) |
|
|
|
|
(3) 18 (2−38) |
|
OR (for each year of age) |
|
|
|
|
|
|
1.19 (95%CI 1.11-1.28) |
|
|
|
|
|
|
OR (for each 1 mmol of mandelic acid per gram of urinary creatinine) |
|
|
|
|
|
|
2.44 (95%CI 1.01-5.89). |
|
|
|
|
|
|
OR (for each 1dB of noise > 85 dB) |
|
|
|
|
|
|
1.18 (95%CI 1.01-1.34) |
Sulkowski et al. (2002)18. Sulkowski WJ, Kowalska S, Matyja W, Guzek W, Wesolowski W, et al. Effects of occupational exposure to a mixture of solvents on the inner ear: a field study. Int J Occup Med Environ Health. 2002;15(3):247-56.
|
Solvent mixture: |
Poland/Cross-sectional |
101 men/Not informed/Paint and varnish company |
(1) 61 exp. solvents (39.8±11.2 years) |
PTA |
HL (above 1 kHz) |
|
- ethylbenzene; |
|
|
(2) 40 non-exposed (39.2±10.5 years) |
TEOAE, DPOAE |
(1) 42% |
|
- xylene; |
|
|
(1a) 20 |
Acoustic reflexes |
(2) 5% |
|
- trimethylbenzene isomers; |
|
|
(1b) 23 |
ENG |
DPOAE amplitude - dBNPS |
|
- toluene; |
|
|
(1c) 18 |
|
(1a) 1,99±6,14 |
|
- ethyl toluene; |
|
|
Length of employment |
|
(1b) -0,31±10,90 |
|
- styrene; |
|
|
(1) 15.8±9.1 years |
|
(1c) -2,87±9,06 |
|
- n-propylbenzene. |
|
|
|
|
(2) 7,48±4,67 |
Sliwinska-Kowalska et al. (2003)11. Sliwinska-Kowalska M, Zamyslowska-Szmytke E, Szymczak W, Kotylo P, Fiszer M, et al. Ototoxic effects of occupational exposure to styrene and co-exposure to styrene and noise. J Occup Environ Med. 2003;45(1):15-24.
|
Noise/Styrene/Solvent mixture: |
Poland/Cross-sectional |
513 (men and women)/Not informed/ |
(1) 157 non-exposed |
PTA (1-8 kHz) |
HL (1 - 8kHz)/OR - HL: |
|
- styrene (main compound); |
|
Exposed to solvents: plastic factory and yacht yard. Non-exposed: |
(2) 356 exposed |
|
(1) 93 (41.7%) |
|
- toluene; |
|
- subgroup 1: blue-collar workers; |
(2a) 194 exp. styrene |
|
(2) 183 (63.1%)/3.9 (95%CI 2.4-6.2) |
|
- acetone; |
|
- subgroup 2: metals. |
(2b) 66 exp. noise |
|
(2a) 56.2%/5.2 (95%CI 2.9-8.9) |
|
- dichloromethane. |
|
|
(2c) 26 exp. styrene + toluene |
|
(2b) 63.3%/3.4 (95%CI 1.7-6.4) |
|
|
|
|
(2d) 56 exp. styrene + noise |
|
(2c) 76.8%/13.1 (95%CI 4.5-37.7) |
|
|
|
|
(2e) 14 exp.styrene + toluene + noise |
|
(2d) 76.9%/10.9 (95%CI 4.9-24.2) |
|
|
|
|
|
|
(2e) 78.6%/21.5 (95%CI 5.1-90.1) |
|
|
|
|
|
|
Styrene and noise |
|
|
|
|
|
|
OR: 3 |
|
|
|
|
|
|
Auditory threshold average in all frequencies: |
|
|
|
|
|
|
Exposed to solvents was significantly higher |
|
|
|
|
|
|
No dose-response relation for HL and solvent concentrations. |
|
|
|
|
|
|
Positive linear relation between lifetime exposure average (styrene) and auditory thresholds at 6 and 8kHz |
|
|
|
|
|
|
Difference between groups |
|
|
|
|
|
|
- Previous exposure to occupational noise (p< 0.001): |
|
|
|
|
|
|
(1) 6% |
|
|
|
|
|
|
(2) 28% |
Chang et al. (2003)28. Chang SJ, Shih TS, Chou TC, Chen CJ, Chang HY, Sung FC. Hearing loss in workers exposed to carbon disulfide and noise. Environ Health Perspect. 2003;111(13):1620-24.
|
Noise/Carbon dissulfide |
Taiwan/Cross-sectional |
346 men/Sudy group: census. Control groups: (3) random and (2) census/ |
(1) 131 exp. noise + carbon dissulfide |
PTA (0.5-8 kHz) |
HL /OR - HL |
|
|
|
Viscose manufacturing plant (1) (3). electronics and adhesive tape industries (2) |
(48.3±8.7 years) |
|
(1) 67.9 %/6.8 (95%CI 3.9-12.1) |
|
|
|
|
(1a) 41: <14.6 ppm + ≤85 dB(A) |
|
(1a) 1.7 (95%CI 0.8-3.7) |
|
|
|
|
(1b) 5: <14.6 ppm + >85 dB(A) |
|
(1b) 0.8 (95%CI 0.1-7.5) |
|
|
|
|
(1c) 24: ≥14.6 ppm + ≤85 dB(A) |
|
(1c) 35.5 (95%CI 7.8-161.3) |
|
|
|
|
(1d) 61: ≥14.6 ppm + >85 dB(A) |
|
(1d) 18.7 (95%CI 8.1-42.9) |
|
|
|
|
(2) 105 exp. noise |
|
(2) 32.4% |
|
|
|
|
(42.2±5.8 years) |
|
(3) 23.6% |
|
|
|
|
(3) 110 non-exposed |
|
HL - 40-54 dBNA |
|
|
|
|
(42.0±6.2 years) |
|
(1) 18% (noise≤85 dB(A)) |
|
|
|
|
Length of employment: |
|
(2) 4% |
|
|
|
|
(1) 20.8±10.5 years |
|
HL 0.5. 1 e 2 kHz: (1) |
|
|
|
|
(2) 21±5.7 years |
|
HL 4 kHz: (2) |
|
|
|
|
(3) 11.3±6.4 years |
|
HL 6 kHz: (1) e (2) |
Sliwinska-Kowalska et al. (2004)12. Sliwinska-Kowalska M, Zamyslowska-Szmytke E, Szymczak W, Kotylo P, Fiszer M, et al. Effects of coexposure to noise and mixture of organic solvents on hearing in dockyard workers. J Occup Environ Med. 2004;46(1):30-8.
|
Noise/Solvent mixture: |
Poland/Cross-sectional |
906 (men and women)/Not informed/ |
Controls of the same company |
PTA (1-8 kHz) |
HL/OR - HL: |
|
- xylene isomers; |
|
Exposed: dockyard. |
(1) 517 exp. noise + solvent (37.4±9.2 years) |
|
(1) 67.5 %/4.8 (IC 95% 3.9-7.6) |
|
- ethylbenzene; |
|
Not exposed: white-collar workers. |
(2) 184 exp. noise (42.2±9.3 years) |
|
(2) 64.7 %/3.3 (IC 95% 2.0-5.4) |
|
- ethyl acetate; |
|
|
(3) non-exposed (39.8±.3 years) |
|
(3) 39.5 % |
|
- butyl acetate; |
|
|
|
|
OR for each year of age: 1.12 |
|
- n-butanol; |
|
|
|
|
OR for for each dB(A) average of total exposure time to noise: 1.07 |
|
- white spirit. |
|
|
|
|
OR for each increase in lifetime exposure index to solvents: 1.00 |
|
|
|
|
|
|
Lower thresholds for (1) and (2), especially at 8 kHz (worst at (1) - positive linear correlation with exposure time to solvents) |
|
|
|
|
|
|
|
Kim et al. (2005)31. Kim J, Park H, Ha E, Jung T, Paik N, Yanh S. Combined effects of noise and mixed solvents exposure on the hearing function among workers in the aviation industry. Ind Health. 2005;43(3):567-73.
|
Noise/Solvent mixture: |
Korea/Cross-sectional |
328 men/Convenience/ Aircraft industry |
According to "Cumulative exposure index": |
PTA (0.5 - 8 kHz) |
HL/OR (adjusted) for HL: |
|
- toluene; |
|
|
(1) 151 non-exposed (31.1±6.3 years) |
|
(1) 6.0% |
|
- xylene; |
|
|
(2) 146 exp. noise (31.2±6.1 years) |
|
(2) 17.1%/4.8 (IC 95% 1.71-10.75) |
|
- methyl ethyl ketone |
|
|
(3) 18 exp. solvent (38.6±6.0 years) |
|
(3) 27.8%/2.57 (IC 95% 0.64-10.31) |
|
(all samples). |
|
|
(4) 13 exp. noise + solvent (39.6±4.7 years) |
|
(4) 54.6%/8.12 (IC 95% 2.03-32.53) |
Kaufman et al. (2005)32. Kaufman LR, Lemasters GK, Olsen DM, Succop P. Effects of concurrent noise and jet fuel exposure on hearing loss. J Occup Environ Med. 2005;47(3):212-18.
|
Noise/Solvent mixture: |
USA/Cross-sectional |
138 workers/Not informed/Military facility (aircraft maintenance and other workers) |
(1) 90 exposed |
Automatic PTA (0.5-6 kHz) |
OR for HL by combined "noise and solvent" exp.: |
|
- benzene; |
|
|
(42.8±6.0 years) |
|
03 years - 1.70 (95%CI 1.14-2.3) |
|
- toluene; |
|
|
(2) 48 non-exposed |
|
12 years - 8.25 (95%CI 1.67-55.6) |
|
- xylene; |
|
|
(40.8±9.9 years) |
|
OR for regular intake of alcoholic beverage: 3.03 (IC95% 1.42-6.45) |
|
- hexane; |
|
|
Years of employment: |
|
|
|
- heptane; |
|
|
(1) 15.8±5.4 |
|
|
|
- kerosene (aviation). |
|
|
(2) 15.6±7.2 |
|
|
Seeber et al. (2005)26. Seeber A, Demes P, Kiesswetter E, Schäper M, Van Thriel C, Zupanic M. Changes of neurobehavioral and sensory functions due to toluene exposure below 50 ppm? Environ Toxicol Pharmacol. 2005;19(3):635-43.
|
Toluene |
Germany/ Retrospective cohort (5 years of follow-up) |
216 workers (initially: 333 workers)/ Convenience/Printing plant |
(1) 106 high exp. |
PTA (0.125; 0.25; 0.5; 0.75; 1; 1.5; 2 - 12 kHz) |
"Cases" |
|
|
|
|
(2) 86 low exp. |
|
(1) 29 |
|
|
|
|
(a) short exp. |
|
(2) 28 |
|
|
|
|
(b) long exp. |
|
OR: 0.791 (95%CI 0.42-1.50) |
|
|
|
|
Exposure time - average: |
|
|
|
|
|
|
(a) 6 years |
|
|
|
|
|
|
(b) 21 years |
|
|
Sliwinska-Kowalska et al. (2005)13. Sliwinska-Kowalska M, Zamyslowska-Szmytke E, Szymczak W, Kotylo P, Fiszer M, et al. Exacerbation of noise-induced hearing loss by co-exposure to workplace chemicals. Environ Toxicol Pharmacol 2005;19(3):547-53.
|
Noise/Solvent mixture: |
Poland/Cross-sectional |
1117 workers/Not informed/ |
(1) 731 exp. solvent mixture (xylene) |
PTA (1; 1.5-8 kHz) |
HL/OR/ PTA freqs.: |
|
- xylene as main component; |
|
(1) (2) (3): lacquers and paints, footwear, plastics, ship and yacht. (4a): metal factory. (4b): white-collar workers |
(38.0±9.4 years) |
|
(1) 63.1%/2.4 (p<0.001)/4; 6 e 8 kHz |
|
- mainly to styrene; |
|
|
(2) 290 exp. styrene |
|
(2) 63.1%/3.9 (p<0.001)/1-8 kHz |
|
- n-hexane and toluene. |
|
|
(34.5±7.9 years) |
|
(3) 73%/5.3 (p<0.001)/6 e 8 kHz |
|
|
|
|
(3) 96 exp. n-hexane and toluene |
|
(4) 41.7% |
|
|
|
|
(39.0±8.7 years) |
|
Only exp. to solvents |
|
|
|
|
(4) 223 non-exposed to solvents |
|
OR: 4.1-5.2 times greater than controls |
|
|
|
|
(40.0±9.4 years) |
|
Only exp. to noise |
|
|
|
|
(4a) 66 exp. noise |
|
OR: 3.8 times greater than controls |
|
|
|
|
(4b) 157 non-exp. noise |
|
Co-exp. to "noise e solvent" |
|
|
|
|
|
|
OR: 6.7-21.5 |
|
|
|
|
|
|
Co-exp. to "noise and two solvents" |
|
|
|
|
|
|
OR: 20 |
Chang et al. (2006)16. Chang SJ, Chen CJ, Lien CH, Sung FC. Hearing loss in workers exposed to toluene and noise. Environ Health Perspect. 2006;114(8):1283-6.
|
Noise/Toluen |
Taiwan/Cross-sectional |
174 men/Census/Adhesive material manufacturing |
(1) 58 exp. toluene + noise |
PTA (0.5-6 kHz) |
HL - including 0.5 kHz/excluding 0.5 kHz |
|
|
|
|
(1a) |
|
(1) 86.2%/67.2% |
|
|
|
|
(1b) |
|
(2a) 44.8%/32.8% |
|
|
|
|
(1c) |
|
(2b) 5.0%/8.3% |
|
|
|
|
(2) 118 reference |
|
OR - including 0.5 kHz/excluding 0.5 kHz |
|
|
|
|
(2a) 58 exp. noise |
|
(1) 10.9 times higher than (2a)/5.8 times higher than (2a) |
|
|
|
|
(2b) 60 management |
|
Poor thresholds in all frequencies, markedly at 4 and 6 kHz, for (1) e (2a), with 1 kHz worse in (1). |
|
|
|
|
Average age: |
|
Adjusted OR - including 0.5 kHz/excluding 0.5 kHz (1) 140 (95%CI 32.1-608)/29.1 (95%CI 9.3-91.4) |
|
|
|
|
(1) 40.0±9.7 |
|
|
|
|
|
|
(2a) 41.5±3.1 |
|
|
|
|
|
|
(2b) 40.9±3.4 |
|
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|
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Length of employment: |
|
|
|
|
|
|
(1) 12.3±8.81 |
|
|
|
|
|
|
(2a) 11.5±5.73 |
|
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|
(2b) 9.52±5.26 |
|
|
Johnson et al. (2006)21. Johnson AC, Morata TC, Lindblad AC, Nylen PR, Svensson EB, Krieg E, Aksentijevic A, Prasher D. Audiological findings in workers exposed to styrene alone or in concert with noise. Noise Health. 2006;8(30):45-57.
|
Noise/Styrene |
Sweden/Cross-sectional |
313 (278 men; 35 women)/ (1) convenience; (2) equal selection to (1); (3) random/ |
(1) |
PTA (0,1-8 kHz) |
PTA |
|
|
|
(1) fiberglass products manufacturing; (2) metal products manufacturing; (3) mail terminal |
(1a) 89 exp. to styrene (43 years (21-62)) |
DPOAE |
(1) > thresholds at 2, 3, 4 and 6 kHz (p<0.05), being worse than median at 4. 6 and 8 kHz (p<0.01). |
|
|
|
|
(1b) 81 exp. to styrene and noise (43 years (21-65)) |
MTF |
(2) thresholds worse than median at 6 and 8 kHz (p<0.01; p< 0.05) |
|
|
|
|
(2) 65 exp. to noise (42 years (20-64)) |
ACR |
PTA after 03 years: 20% of individuals with worse auditory thresholds at one frequency at least |
|
|
|
|
(3) 78 non-exposed (45 years (26-62)) |
IS |
MTF - threshold average |
|
|
|
|
Length of employment - years: |
Speech in noise |
Significant difference between (1b) and (3) and between (1b) and (2), with reduced peak values for (2) |
|
|
|
|
(1) |
|
DPOAE - "input-output" |
|
|
|
|
(1a) 17 (01-39) |
|
Interaction between exposed groups and signal level (p<0.006) |
|
|
|
|
(1b) 15 (02-37) |
|
- signal up to 50 dB: (2) and (3) DPOAE higher than (1) |
|
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|
|
(2) 12 (01-35) |
|
- signal > 50 dB: (3) DPOAE level stabilized, (1) and (2) fell |
|
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|
(3) 18 (2-38) |
|
ACR |
|
|
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|
|
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(1) and (2) difference over latency score (p<0.05) compared to (3) |
|
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|
|
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Interrupted speech |
|
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No difference in score average between groups |
|
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Compared to reference values: (1) below 93% or 78% of corrects answers (p<0.05) |
|
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Speech in noise |
|
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Difference between groups (p<0.001) |
|
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Compared to reference values: (1) and (2) below - 7.8 S/N (p<0.05) |
Schäper, Seeber e Van Thriel (2008)25. Schäper M, Seeber A, Van Thriel C. The effects of toluene plus noise on hearing thresholds: an evaluation based on repeated measurements in the German printing industry. Int J Occup Med Environ Health. 2008;21(3):191-200.
|
Noise/Toluene |
Germany/Cohort (5 years) |
Men |
Follow-ups: |
PTA (0.125-0.5; 0.75; 1; 1.5; 2-8; 12 kHz) |
PA: 36% |
|
|
|
Initial total: 333 (100%) |
- initial: 333 (100%) |
|
Effect of noise intensity on threshold average was almost twice the effect of toluene intensity. |
|
|
|
Final total: 216 (64,9%) |
- 2: 278 (83.5%) |
|
Differences between exposure level or length in cases and noncases were not significant (p = 0.49; p = 0.51 respectively). |
|
|
|
(complete data for 192 participants)/Convenience/ Rotogravure printing |
- 3: 241 (72.4%) |
|
HL high frequencies (subsample with biomarkers): 36% |
|
|
|
|
- 4: 216 (64.9%) |
|
No exposure variable found any significance in the statistical model. |
|
|
|
|
Complete data for 192 participants |
|
|
|
|
|
|
Stratification by intensity of exp. to toluene: |
|
|
|
|
|
|
(1) 106 high exp. |
|
|
|
|
|
|
(2) 86 low exp. |
|
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|
|
|
Stratification by length of exp. to toluene: |
|
|
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|
|
|
(3) long exp. |
|
|
|
|
|
|
(4) short exp. |
|
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|
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Stratification by intensity of exp. to noise: |
|
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|
|
|
(5) high exp. |
|
|
|
|
|
|
(6) low exp. |
|
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Exposure time to toluene and noise - years: |
|
|
|
|
|
|
(3) 21.3±6.5 |
|
|
|
|
|
|
(4) 5.9±2.2 |
|
|
Rabinowitz et al. (2008)33. Rabinowitz PM, Galusha D, Slade MD, Dixon-Ernst C, O'Neill A, Fiellin M, Cullen MR. Organic solvent exposure and hearing loss in a cohort of aluminium workers. Occup Environ Med. 2008;65(4):230-5.
|
Noise/Carbon Monoxide/Solvent mixture: |
USA/Retrospective cohort (5 years) |
1319 (men and women)/ Census/Aluminium industry |
1319 subjects |
PTA |
OR (HL dichotomous outcome/exp.>5 years) |
|
- toluene; |
|
|
(30.4±3.7 years): 1167 men |
|
(1) 1.87 (95%CI 1.22-2.89; p=0.04) |
|
- xylene; |
|
|
(1) 116 (8.8%) solv. exp. |
|
|
|
- methyl ethyl ketone. |
|
|
(solv. exp. index >1) |
|
|
|
|
|
|
(2) 140 (10.6%) carbon monoxide exp. |
|
|
|
|
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|
(solv. exp. index >1) |
|
|
Triebig, Bruckner e Seeber et al. (2008)22. Triebig G, Bruckner T, Seeber A. Occupational styrene exposure and hearing loss: a cohort study with repeated measurements. Int Arch Occup Environ Health. 2008;82(4):463-80.
|
Styrene |
Germany/Cross-sectional - with repetition measures |
155 men/Census/Boat building |
- 128 more exp. styrene |
PTA PTA high freqs. (9-16 kHz) TOAE |
HL: 105 "cases"/132 "non-cases" |
|
|
|
|
- 127 less exp. (5-25 ppm (below 200mg/g creat.)) |
|
High exp.: 55%/45% |
|
|
|
|
According to biomarkers - all participants: |
|
Low exp.: 41%/59% |
|
|
|
|
(1a) 99 low exp. (37.8±8.9 years) |
|
(2a) 35%/65% |
|
|
|
|
(1b) 118 medium exp. (38.5±8.9 years) |
|
(2b) 60%/40% |
|
|
|
|
(1c) 31 high exp. (37.9± 11years) |
|
Auditory thresholds (dB) between 8 e 12.5 kHz slightly different between the high and low exposure groups, with no dose-response effect. |
|
|
|
|
According to exposure length - " extreme groups": |
|
Change in chronic exposure from (2a) to (2b): OR 7.46 (IC>1) for HL |
|
|
|
|
(2a) 34 "low-short" exp. (42.6±8.4 years) |
|
TEOAE |
|
|
|
|
(2b) 17 "high-long" exp. (43.5±11.1 years) |
|
No direct association between the groups and S/N relation or amplitude. |
|
|
|
|
Length of employment - years: |
|
|
|
|
|
|
(1a) 6.2±4.3 (1-26) |
|
|
|
|
|
|
(1b) 5.7±3.6 (1-23) |
|
|
|
|
|
|
(1c) 6.3±4.8 (1-26) |
|
|
|
|
|
|
(2a) 6.4±3.4 (2-16) |
|
|
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|
|
|
(2b) 14.6±6.7 (10-26) |
|
|
Fuente et al. (2009)34. Fuente A, Slade MD, Taylor T, Morata TC, Keith RW, Sparer J, Rabinowitz PM. Peripheral and central auditory dysfunction induced by occupational exposure to organic solvents. J Occup Environ Med. 2009;51(10):1202-11.
|
Solvent mixture: |
New Haven - USA/ Cross-sectional |
110 participants/Census/ Coating factory |
(1) 20 minimum exp. (38.1±11.6 years; 12 women. 08 men) |
PTA (0,5-8 kHz) |
Altered PTA in 69 subjects/Altered PTA high freqs. in 22 subjects |
|
- toluene; |
|
|
(2) 18 moderate exp. (41.0±12.4 years; 01 woman. 17 men) |
PTA high freqs. (12 and 16 kHz) |
(1) 25% |
|
- methyl ethyl ketone. |
|
|
(3) 72 maximum exp. (39.5±11.4 years. 04 women . 68 men) |
DD |
(2) 61%/16.6% |
|
Less quantity: |
|
|
(categorized by a hygeniest) |
|
(3) 73.6%/26.4% |
|
- trichlorethylene; |
|
|
|
|
(1) thresholds better than (3) (PTA p=0.004; PTA high freqs. p=0.034) |
|
- acetone; |
|
|
|
|
DD |
|
- n-methyl-pyrrolidone; |
|
|
|
|
(1) better responses than (2) (p=0.001) and (3) (p=0.000) |
|
- dimethylformamide; |
|
|
|
|
Estimate for subjects with normal PTA: (2) -0.382(3) - 0.471 |
|
-clorobenzeno; |
|
|
|
|
Estimate for all subjects: (2) -0.274(3) - 0.386 |
|
- isopropyl alcohol. |
|
|
|
|
|
Zamyslowska-Szmytke et al. (2009)23. Zamyslowska-Szmytke E, Fuente A, Niebudek-Bogusz E, Sliwinska-Kowalska M. Temporal processing disorder associated with styrene exposure. Audiol Neurootol, 2009;14(5):296-302.
|
Styrene |
Poland/Cross-sectional |
109 workers/Not informed/ Fiberglass for manufacturing |
(1) 59 exp. styrene (40±09 years; 6 women, 53 men) |
PTA (0.125-8 kHz) |
PTA |
|
|
|
|
(2) 50 non-exposed (37±11 years; 16 women, 34 men) |
GIN |
(1) worse thresholds (0.25-8kHz) |
|
|
|
|
|
FPT |
(1) 86.4% |
|
|
|
|
|
DPT |
(2) 34% |
|
|
|
|
|
|
GIN/FPT /DPT |
|
|
|
|
|
|
(1) worse averages |
|
|
|
|
|
|
(1) 24%/59%/85% |
|
|
|
|
|
|
(2) 12%/20%/26% |
|
|
|
|
|
|
(1) Chi-square/ANCOVA adjusted for age and HL |
|
|
|
|
|
|
FPT: 11.7 (p<0.01) /6.8 (p<0.01) |
|
|
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|
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DPT: 26.4 (p<0.01) /19.3 (p<0.001) |
|
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|
|
GIN: 1.2 (p>0.05) |
Guest et al. (2010)29. Guest M, Bogges M, Attia J, D'Este C, Brown A, Gibson R, et al. Hearing impairment in F-111 maintenance workers: the study of health outcomes in aircraft maintenance personnel (SHOAMP) general health and medical study. Am J Ind Med. 2010;53(11):1159-69.
|
Noise/Aircraft fuel (F-111) |
Australia/Cross-sectional (with serial measurements) |
1530 workers/(1) convenience; (2) (3) random/Royal Australian Air Force |
(1) 605 exposed (98% men; 87%<55years) |
PTA (0.5; 1; 1.5-8 kHz) |
Overall HL: 25% of clinically significant difference (compensation). |
|
|
|
|
(2) 510 technical comparison - different base, same function (99% men; 91%<55years) |
|
PTA |
|
|
|
|
(3) 398 no technical comparison - same base, different function (99% men; 90%<55years ) |
|
(0.5; 1; 1.5-8 kHz) worse than normalcy standard (presence of a noise notch at 6 kHz) |
|
|
|
|
|
|
OR for HL: similar among the three groups |
|
|
|
|
|
|
(2) 1.1 (CI95% 0.2-2.0) |
|
|
|
|
|
|
(3) 0.9 (CI95% 0.6-1.3) |
Mohammadi, Labbafinejad e Attarchi et al. (2010)40. Mohammadi S, Labbafinejad Y, Attarchi M. Combined effects of ototoxic solvents and noise on hearing in automobile plant workers in Iran. Arh Hig Rada Toksikol. 2010;61(3):267-74.
|
Noise/Solvent mixture: |
Iran/Cross-sectional |
441 men/Census/ Automobile plant |
Average age: (33.07 years; 20-58 years) |
PTA (0.5-8 kHz) |
HL (average 3-8kHz)/adjusted OR |
|
- benzene; |
|
|
(1) 173 exp. noise (33.36±6.95 years) |
|
(1) 24.08±11.89/1 |
|
- toluene; |
|
|
(2) 104 exp. solvents - within limits (31.87±5.49) |
|
(2) 25.71±7.01/1.8 (95%CI 1.08-3.03) |
|
- xylene; |
|
|
(3) 164 exp. noise + solvents - above limits (33.53±6.22) |
|
(3) 32.77±16.04/4.13 (95%CI 2.59-6.58) |
|
- tetrachlorethylene; |
|
|
Length of employment: |
|
(3) more common (p<0.001)) |
|
- acetone. |
|
|
8.06 years (0.5 a 30 years) |
|
|
Beshir, Elserougy e Amer (2011)35. Beshir S, Elserougy SM, Amer NM. Ototoxic and ototraumatic effects of organic solvents and occupational noise in ceramic workers. Aust J Basic Appl Sci. 2011;5(12):21-8.
|
Noise/Solvent mixture: |
Sadat - Egypt/ Cross-sectional |
204 men/(1) census; (2) (3) not informed/Ceramics plant |
(1) 44 exp. solvent mixture (36±2 years) |
PTA (0.25-2; 4; 8 kHz) |
HL - 0.5; 1 and 4 kHz |
|
- acetone; |
|
|
(2) 73 exp. noise (38.1±7.3 years) |
|
(1) 72.7%; 45.5%; 45.5% |
|
- butanol; |
|
|
(3) 87 non-exposed (37±3.5 years) |
|
(2) 94.5%; 69.9%; 67.1% |
|
- ethanol; |
|
|
Length of exposure: |
|
(p<0.05) |
|
- ethyl acetate; |
|
|
(1) 16±6 |
|
(1) more common at 8 kHz than 4 kHz |
|
- isopropanol; |
|
|
(2) 15±9 |
|
(2) more common at 4 kHz than 8 kHz |
|
- toluene; |
|
|
|
|
v-notched |
|
- xylene. |
|
|
|
|
(1) 63.3% |
|
|
|
|
|
|
(2) 31.5% |
|
|
|
|
|
|
(p<0.01) |
|
|
|
|
|
|
Correlation between exp. length and freqs. of 4 and 8 kHz (adjusted) |
|
|
|
|
|
|
(1) 0.795 (p=0.000) and 0.869 (p=0.000) |
Fuente, Mcpherson e Hickson (2011)36. Fuente A, Mcpherson B, Hickson L. Central auditory dysfunction associated with exposure to a mixture of solvents. Int J Audiol. 2011;50(12):857-65.
|
Solvent mixture: |
Chile/Cross-sectional |
92 workers/(1) not informed; (2) convenience/ (1) paint factories; (2) University of Chile/Chilean police officers |
(1) 46 exp. solvent mixture (37.3±8.2 years; 41 men and 05 women) |
PTA (0.5-8 kHz) |
Normal auditory thresholds (inclusion criterion), but worse for (1) at freqs. of 1, 2 and 3 kHz. |
|
- toluene; |
|
|
(2) 46 non-exposed (36.1±6.1 years; 41 men and 5 women) |
RGD |
Score differences between groups (adjusted) |
|
- xylene; |
|
|
Length of exposure: |
MLD |
DD (F=4.77; p=0.032) |
|
- methyl ethyl ketone; |
|
|
(1) 02 to 30 years (13.3±8.2 years) |
PPS |
PPS (F=2.87; p=0.014) |
|
- varsol. |
|
|
|
DD |
FS (F=5.85; p<0.0001) |
|
|
|
|
|
FS |
RGD (1; 2; 4 kHz) (F=3.22; 2.83; 4.20 p<0.02, respectively) |
|
|
|
|
|
HINT |
HINT SRT (F= 13.3 p<0.0001) |
|
|
|
|
|
|
No statistically significant difference was observed for MLD and HINT (speech-in-noise subtests) |
Morata et al. (2011)24. Morata TC, Sliwinska-Kowalska M, Johnson A-C, Starck J, Pawlas K, Zamyslowska-Szmytke E, et al. A multicenter study on the audiometric findings of styrene-exposed workers. Int J Audiol. 2011;50(10):652-60.
|
Noise/Styrene |
Finland, Sweden and Poland/Cross-sectional |
Initial totall: |
(1) 423 exp. solvents |
PTA (0.125-8 kHz) |
(1) and (2) worse thresholds than reference standard at all frequencies. |
|
|
|
1620 workers (1276 men; 312 women; 32 gender not informed). Final total: 1404 workers/Not informed/ Fiberglass products plants; industries: metal, wood products, yacht yard and office work. |
(2) 268 exp. noise + solvents |
|
(1) p=0.0001 |
|
|
|
|
(3) 359 exp. noise |
|
(2) p=0.0192 |
|
|
|
|
(4) 354 non-exposed |
|
OR for HL (for each year of age and each increase of 1 mg/m³ of styrene): |
|
|
|
|
Age - years: 18-63 |
|
(1) 1.0188 (95%CI 1.0140-1.0236) |
|
|
|
|
|
|
(2) 1.0055 (95%CI 1.0009-1.0102) |
|
|
|
|
|
|
(3) 1.01 (95%CI 0.99-1.03) |
Kaewboonchoo et al. (2013)38. Kaewboonchoo O, Srinoon S, Lormphongs S, Morioka I, Mungarndee S. Hearing loss in Thai naval officers of coastal patrol crafts. Asia Pac J Public Health. 2014;26(6):651-9.
|
Noise/Solvent mixture: |
Thailand/Cross-sectional |
149 men/Census/ Thailand Navy officers |
Age: (20-56 years) |
PTA (0.5;1; 2; 4; 8 kHz) |
HL in 40 % of workers |
|
- toluene; |
|
|
Exposed to solvents: 103 (69.1%) |
|
Inclination at 4 kHz: 22.8% |
|
- xylene; |
|
|
Length of employment: 0 |
|
High frequencies: 14.8% |
|
- ethyl acetate; |
|
|
1 a 36 years (31.5%>08 years; 6.9±8.5 years) |
|
Adjusted OR |
|
- butyl acetate; |
|
|
|
|
Age: 15.83 (IC 95% 3.39-73.92) |
|
- cyclohexane. |
|
|
|
|
Length of service: 2.19 (95%CI 1.01-4.97) |
|
|
|
|
|
|
Correlation coefficient adjusted for age |
|
|
|
|
|
|
Length of service - frequency of 4 kHz: 0.108 (p<0.05) |
Fuente, Mcpherson e Cardemil et al.(2013)27. Fuente A, Mcpherson B, Cardemil F. Xylene-induced auditory dysfunction in humans. Ear hear. 2013;34(5):651-60.
|
Misture of xylene isomers |
Santiago - Chile/ Cross-sectional |
60 workers/Convenience/ (1) public hospital histology lab; (2) University of Chile |
(1) 30 exp. xylene (15 men. 15 women; 37.1±10.7 years) |
PTA (0.25-8 kHz) BAEP DPOAE PPS ATTR DD MLD HINT |
HL - 0.5 - 8 kHz |
|
|
|
|
- cumulative dose of methyl hippuric acid: |
|
(1) thresholds worse than (2) |
|
|
|
|
(1a) 10 |
|
DPOAE adjusted for age |
|
|
|
|
(1b) 10 |
|
No statistically significant difference between (1) and (2) |
|
|
|
|
(1c) 10 |
|
(associated age p≤0.001) |
|
|
|
|
(2) 30 non-exposed (15 men. 15 women. 35.9 ±11.7 years) |
|
BAEP adjusted for age |
|
|
|
|
- comared to study subgroups: |
|
(1) greater latencies I, III e V) and inter-peak intervals (I-III, III-V e I-V) (p=0.001) |
|
|
|
|
(2a) 10 |
|
(age not statistically associated) |
|
|
|
|
(2b) 10 |
|
Score difference between groups (adjusted for age) |
|
|
|
|
(2c) 10 |
|
PPS (F=8.04 p<0.01) |
|
|
|
|
Length of exposure (self-reported): |
|
DD (F=9.03 p<0.01) |
|
|
|
|
11.8±10.5 years (02-29 years) |
|
HINT (final score) (F=13.77; p<0.0001) |
|
|
|
|
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No statistically significant difference was observed for MLD, ATTR e HINT SRT (p>0.05) |
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(age associated with HINT (final score) and PPS (p<0.01 and p<0.0001, respectively)) |
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BEI in (1) |
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Moderate positive correlation between BEI (p=0.42) and binaural average of hearing levels at 2-8kHz (p=0.02). BEI concentrations predicted the binaural average of hearing levels (β=0.59. p<0.01): for each 1g/g of creatinine, increase of 0.034 dBNA. |
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No correlation with the remaining procedures (p>0.05) |
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Dose-response effect and PTA - average |
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(1a) 8.1±6.7 |
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(1b) 9.0±3.9 |
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(1c) 20.7±9.1 |
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((1a) e (1b) significantly different from (1c)) |
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(1c) different from (2) (p<0.01) |
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Dose-response effect and DPOAE - average |
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(1a) 4.15±8.78 |
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(1c) -4.04±6.03 |
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((1a) e (1c) significantly different) |
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(1b) -0.57±5.39 |
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There was no significant difference between the subgroups |
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"Dose-response effect" subgroups and the remaining procedures. |
Fuente, Mcpherson e Hickson (2013)36. Fuente A, Mcpherson B, Hickson L. Central auditory dysfunction associated with exposure to a mixture of solvents. Int J Audiol. 2011;50(12):857-65.
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Solvent mixture: |
Santiago - Chile/ Cross-sectional |
144 workers/convenience/ Paint factory |
(1) 72 exp. solvents (66 men. 6 women; 39.9±8.5 years) |
PTA (0.25-8 kHz) |
PTA |
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- methyl ethyl ketone; |
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(2) 72 non-exposed (58 men. 14 women; 37.5±7.1years) |
BAEP |
(1) worse thresholds (1, 2, 3 and 8 kHz) than (2) (p<0.003) |
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- tolueno; |
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Length of employment - exp. to solvents: |
TEOAE |
TEOAE |
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- xylene; |
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(1) 15.8±8.1 years |
RGD |
(1) worse S/R ration than (2) (p<0.01) |
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- thinner (Stoddard solvent -mineral spirit); |
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HINT |
CAP testing |
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less quantity: |
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Worse scores (1) for RGD, HINT SRT, HINT1, HINT 2 and HINT (final score) - (p<0.05) |
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- benzol; |
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No statistically significant difference between was observed for HINT3 (p>0.05) |
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- esters; |
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- alcohol. |
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Fuente, Mcpherson e Hormazabal et al. (2013)37. Fuente A, Mcpherson B, Hormazabal X. Self-reported hearing performance in workers exposed to solvents. Rev Saúde Pública. 2013;47(1):86-93.
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Solvent mixture: |
Santiago - Chile/ Cross-sectional |
96 workers/census/Paint factory |
(1) 48 exp. solvents (38.6±7.1 years) |
PTA (0.5-8 kHz) RGD AIADH |
PTA - threshold average (dBNA) OD/OE |
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- methyl ethyl ketone; |
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(2) 48 non-exposed (36.8±4.8years) |
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(1) 9.2±5.6/10.1±5.6 (worse thresholds at 0.5-4 kHz) |
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- toluene; |
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Length of exp. to solvents: |
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(2) 7.1±4.3/8.4±4.1 |
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- xylene; |
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(1) 13.5 years |
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None of the subjects showed HL according to WHO |
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- Stoddard solvent. |
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RGD |
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(1) worse results |
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(difference between (1) and (2) (p<0.05)) |
Hughes e Hunting (2013)8. Hughes H, Hunting KL. Evaluation of the effects of exposure to organic solvents and hazardous noise among US Air Force Reserve personnel. Noise Health. 2013;15(67):379-87.
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Noise/JP -8 (aircraft kerosene)/Solvent mixture: |
USA/Retrospective cohort (3.2 years) |
503 workers (94,6% male)/ Not informed/US Air Force Reserve |
(1) 148 exp. noise |
PTA 0.25-8 kHz shift threshold standard (STS): |
Shift threshold standard (STS) - average of worse ear not informed: |
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- toluene; |
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(2) 65 exp. solvents |
≥ 10dB, in either ear, between 2 and 4 kHz, based on reference exam. |
(1) 11±7.4 |
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- styrene; |
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(3) 220 exp. noise + solvents |
Categories: |
(2) 3±4.6 |
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- xylene; |
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(4) 70 non-exposed (94.6% men) |
- STS (≥10 dB) |
(3) 12±5.5 |
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- benzene. |
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Age (years) at date of first audiogram - median: |
- hearing loss (>0 a <10 dB) |
(4) 6±8.6 |
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(1) 28.5±8.5 |
- no hearing loss (≤0 dB) |
RR for HL - worse ear: |
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(2) 34.0±8.7 |
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(1) 1.1 (CI95% 0.9-1.4) |
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(3) 30.5±8.4 |
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(2) 0.8 (CI95% 0.6-1.2) |
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(4) 30.0±10.0 |
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(3) 1.2 (CI95% 0.9-1.5) |
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Length of follow-up - years: |
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(4) 1.1 (CI95% 0.7-1.5) |
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(1) 3.5±2.4 |
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Study follow-up length associated with increased HL chance (OR=1.23.CI95% 1.12 - 1.35) for each follow-up year. |
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(2) 1.8±1.7 |
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(3) 3.3±2.0 |
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(4) 3.4±1.7 |
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