Mercury : the beginnings in the medicalization of common names of medicinal plants in Brazil

Medicalization of common names of medicinal plants is a process that involves replacing popular native names by trademarked names of drugs, active principles or therapeutic indications used by modern biomedicine. In Brazil, this process seems to have been intensified in the early 2000s due to the increasing use of those names in ethnoscientific surveys in local communities. In this study, we aimed to trace the origins of that process. For this purpose, we reviewed data from the “grey literature” pre-1980, including 15 books, compendia, dictionaries, and guides of medicinal plants. Mercury and its lexical changes were the only medicalized names found in the literature before the 1980s. This is probably due to the ancient use of mercury in several medical systems through human history, including by Brazilian apothecaries since the seventeenth century. Moreover, Mercurochrome was the name of a Brazilian trademark of antiseptic that probably influenced the use of medicalized names of mercury in the past. The name “Mercury” and its “natural” epithet combinations, like “Mercúrio-vegetal” (Mercury-plant) and “Mercúriodo-campo” (Field-mercury), could have been the original medicalized way of naming medicinal plants in Brazil.

Several plant species have been assigned with common names similar to those of popular Brazilian drugs, e.g., Terramicine, Anador ® , and Vick ® . This is related to two cultural appropriation processes, the medicalization and pharmaceuticalization, which have been occurring for some decades in Brazil. Medicalization is generally conceptualized as a biomedical transformation of human Pharmacognosy Mercury: the beginnings in the medicalization of common names of medicinal plants in Brazil experiences and behaviors into medical concerns (Bortoli et al. 2019;Zola 1983). On the other hand, pharmaceuticalization can be defined as the overconsumption of pharmaceuticals and social dependency of commercial drugs (Fox & Ward 2008;Bell & Figert 2012).
Medicinal plants with medicalized names can be found cumulatively in ethnobiological surveys from the 1980s to the late 2010s (Siqueira et al. 2018). The medicalized names could have had an ethnotaxonomical origin, associated with extensive drug use by modern societies in the twentieth century (Siqueira et al. 2017(Siqueira et al. , 2018. However, so far, no evidence has been found to support the recency of the medicalization process since, apparently, there are no surveys about it before the 1980s. To trace the origins of the medicalization of common names of medicinal plants in Brazil, we evaluated the presence of medicalized names in the "grey literature" from the early twentieth century. Grey literature is defined as scientific productions that were not formally published, including book chapters, research reports, and other unpublished data (Hopewell et al. 2007). We consulted 15 books, compendia and dictionaries of medicinal plants, including those that were published before the 1980s, such as Correa 1 (1926, 1931, 1952, 1969, 1974, 1975), Da Matta (1913, and Cruz (1979) (Tab. 1). These references were chosen based on their historical relevance in the field of Brazilian medicinal plants and availability.
(mercury) combined with the epithets "vegetal" (plant) and "campo" (field), both indicating natural sources, is the most ancient medicalized name in Brazil. The association of "natural" epithets seems to be a rudimentary method of creating medicalized names in popular Brazilian medicine.
The former practice of naming medicinal plant species as "Mercúrio" is mainly related to the ancient therapeutic use of the mercury element, predominantly extracted from cinnabar (Broussard et al. 2002), in several traditional pharmacopoeias worldwide, like the Caribbean (Zayas & Ozuah 1996), Indian-Tibetan (Kumar & Prabhakar 1987;Leslie 1976), and Chinese (Tang et al. 2008). The therapeutic use of mercury in drug preparations in Brazilian pharmacies and apothecaries dates back to the eighteenth century (Edler 2006), but probably was a common "chemical medicine" since the sixteenth century (Almeida 2017).
The Brazilian Pharmacopoeia also mentioned its use in several pharmaceuticals to treat syphilis and wounds until the 1920s and 1990s, respectively, since the first edition (Silva 1929). This probably explains the majority of popular antisyphilitic indications of species, pre-1980s, listed in Table  2. The "antirheumatic" indications were probably related to congenital and acquired syphilitic arthritis that overcome in several clinical cases of the disease (Gray & Philip 1963), or to the similarity of those symptoms with other musculoskeletal disorders.
On the other hand, pharmacological activities and organoleptic characteristics may explain the case of Erythroxylum suberosum due to the reddish color of the inner bark and its antimicrobial and anti-inflammatory activities (Tab. 2). The red inner bark is a morphological characteristic that could refer to the alcoholic solution of merbromin.  (Fig. 2), a topical antiseptic formerly used to treat wounds and perforations in the epidermis (Campos 1978) (Fig. 3). The main constituent of "Mercúrio-cromo" is Merbromin, a sodium organomercuric compound prohibited as a commercial drug by ANVISA (Brazilian National Health Surveillance Agency) since 2001 (ANVISA 2001). Therefore, the medicalized name "Mercúrio" may become obsolete due to this relatively recent ban on the use of mercury compounds in Brazilian drugs. On the other hand, another medicalized name of antiseptic, "Merthiolate," is derived from the trademark name Merthiolate ® and it has been used to the same therapeutic purposes (Bieski et al. 2015;Caetano et al. 2015;Leite & Oliveira 2012;Martins et al. 2005). In this context, we hypothesize a gradual functional substitution of the name "Mercury" by "Merthiolate" to name medicinal plants with antiseptic and wound-healing properties.