Occurrence and potential risk of triclosan in freshwaters of São Paulo, Brazil—the need for regulatory actions

Abstract

Triclosan (TCS) is a broad-spectrum bactericide, highly toxic to algae, which is released into the environment via wastewater effluents. Predicted no-effect concentrations (PNECs) for aquatic biota have been proposed in the literature, varying from 1.4 to 1,550 ng/L, reflecting contradicting protection goals. In this work, six rivers in the state of São Paulo were monitored for TCS and caffeine, a tracer for untreated sewage disposal, over a period of more than 1 year. From 71 samples analyzed, 32 contained TCS at concentrations above the limit of quantification, ranging from 2.2 to 66 ng/L, corresponding to a frequency of exceedance of the lowest PNEC of 86 % (six out of seven sites). No correlation between TCS and caffeine was observed, and one of the reasons for that could be the different use patterns in the local populations. Given the high values found in the investigated rivers, TCS seems to be a strong candidate in the priority list of compounds that should be regulated in Brazil to preserve the aquatic environment.

Pharmaceuticals and personal care products as emerging micropollutants in Brazilian surface waters: a preliminary snapshot on environmental contamination and risks

“…Triclosan should also be prioritized, since all results generated in the country so far evidence risk or possible risk. An extensive investigation on triclosan in Brazilian waters has already put this substance as a strong candidate in a priority list that must be regulated in Brazil to preserve aquatic environments 57 . Non-prescribed drugs such as acetaminophen, diclofenac and naproxen, as well as the antidepressants carbamazepine and sertraline are not in the top of the rank but may also be candidates to further investigations.…”

Ecological and toxicological responses in a multistressor scenario: Are monitoring programs showing the stressors or just showing stress? A case study in Brazil

“…For this reason, it would be desirable to conduct more frequent intensive monitoring campaigns, in order to update information on the chemical substances present in the reservoirs and other water bodies (at least in those where toxic responses have been observed), and to prioritize those substances or environmental factors known to present human or environmental risks. This type of approach has been widely used in Europe (Guillén et al, 2012), but is very rare in Brazil or other countries of South America (Montagner et al, 2014).…”

Potential endocrine disruptor activity of drinking water samples

“…In the present study, we selected a sampling site that has been extensively evaluated in earlier studies 4,5,7,9,18 to verify if the concentrations of contaminants found in the water could induce endocrine effects in juvenile female rats. As a part of this comprehensive study, raw (untreated) water from Atibaia River showed estrogenic activity when evaluated using the Bioluminescent Yeast Estrogen Assay (BLYES).…”

“…[3][4][5] São Paulo State has only 50% of its sewage production treated, and high levels of different classes of chemicals (pharmaceuticals, personal care products, hormones, drugs of abuse, pesticides, industrial chemicals) have been found in surface and drinking water (DW). [6][7][8][9] As a consequence, humans are continuously exposed to several estrogens, anti-estrogens, androgens, anti-androgens and steroidogenic substances, and this has stimulated interest in assessing the effects associated with simultaneous exposure to these chemicals 10,11 because low concentrations of some environmental contaminants may cause adverse effects both in humans and biota. 12,13 A significant increase in reproductive problems in some regions of the world over the last few decades points to unidentified environmental factors in disease etiology, and ED exposures have recently been linked with obesity, cardiovascular disease, diabetes and metabolic syndrome in human adults.…”

“…In Brasil, water bodies have been chemically evaluated to determine ED contaminant concentrations of chemicals such as triazoles, triazines, strobilurins, organophosphates, phenyl pyrazole, benzimidazole, caffeine, bisphenol A, natural and synthetic hormones, phenols, bactericides, inseticides and herbicides. 4,5,7,9,18 The potential of the concentrations of these contaminants present in 2 DW samples collected at a Water Treatment Plant (WTP) of São Paulo, Brazil to induce endocrine effects in juvenile female rats was measured using the uterotrophic and pubertal female development in vivo rat assays. Additional sensitive end-points were added to identify the mode of action of the effects seen.…”