Exposure to organic solvents and hepatotoxicity

The Comet Assay as a Tool in Human Biomonitoring Studies of Environmental and Occupational Exposure to Chemicals-A Systematic Scoping Review

Biomonitoring of human populations exposed to chemical substances that can act as potential mutagens or carcinogens, may enable the detection of damage and early disease prevention. In recent years, the comet assay has become an important tool for assessing DNA damage, both in environmental and occupational exposure contexts. To evidence the role of the comet assay in human biomonitoring, we have analysed original research studies of environmental or occupational exposure that used the comet assay in their assessments, following the PRISMA-ScR method (preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews). Groups of chemicals were designated according to a broad classification, and the results obtained from over 300 original studies (n = 123 on air pollutants, n = 14 on anaesthetics, n = 18 on antineoplastic drugs, n = 57 on heavy metals, n = 59 on pesticides, and n = 49 on solvents) showed overall higher values of DNA strand breaks in the exposed subjects in comparison with the unexposed. In summary, our systematic scoping review strengthens the relevance of the use of the comet assay in assessing DNA damage in human biomonitoring studies.

Carotenoids obtained from an ionic liquid-mediated process display anti-inflammatory response in the adipose tissue-liver axis

Ionic liquids (ILs) have been proposed as more efficient and sustainable solvents to replace volatile organic solvents (VOSs). However, the drawbacks associated with their use are still limiting the regular application of bioactive compounds obtained from the processes they mediate as food ingredients. It is true that the number of ILs approved by the Food and Drug Administration for food applications is still low and mainly focused on the ones from the quaternary ammonium family. However, this trend is changing, judging from the evidence that industries are surpassing overgeneralization about ILs (on price and toxicity) and starting to consider the potential and performance of ILs as solvents. Despite the examples of industries applying ILs in their processes, the use of bioactive compounds obtained from IL-based processes as ingredients in food formulations is still a big challenge. The positive influence of carotenoids on diseases associated or originating from the inflammatory scenario including, among others, obesity, is not new. Moreover, it is also well known that the poorest population worldwide does not have the recommended intake of carotenoids, especially those pro-vitaminic A. In an attempt to help answer this issue, dietary supplements containing adequate doses of natural carotenoids are expected to be the solution, or at least, part of the solution for a healthier life, but also, to reduce hunger. Thus, complete studies evaluating the toxicological potential and the real viability of adding these bioactive compounds in food formulations proving (or not!) their safety to consumers and handlers are highly demanded. This work proposes to investigate the potential of carotenoids extracted from Bactris gasipaes feedstocks mediated by an ethanolic solution of an imidazolium-based IL. Thus, male Wistar rats were randomized in six different groups, supplemented or not by carotenoids extracted by IL or VOS, and fed by control- and/or high-fat-diets (HFD). The adipose tissue-liver axis was studied as a model to investigate the influence of the carotenoids on the levels of inflammation and oxidative stress markers. The main results showed that animals supplemented with carotenoids extracted with IL displayed improvements in serum parameters, besides lower metabolic efficiency, and antioxidant response on the liver, even when fed with HFD. However, animals supplemented with carotenoids extracted by VOS showed higher levels of pro-inflammatory markers and huge oxidative stress on the liver.

Liver function alterations among workers in the shoe industry due to combined low-level exposure to organic solvents

This study aimed to investigate the potential hepatotoxicity, nephrotoxic, and hematotoxic effects of simultaneous occupational low-level exposure of shoe workers to a mixture of organic solvents. The study included 16 male and 55 female workers and non-exposed subjects (n = 60) in the control group. Along with a standard sets of hematological, liver enzymes (aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyl transpeptidase (GGT), bilirubin total, bilirubin direct, blood glucose, urea, and creatinine were analyzed in all participants. Indoor air quality was monitored using a Gasmet Dx - 4000 multi-component analyzer. Despite the concentration levels of individual chemicals in shoe production units were below the permissible limits, the equivalent exposure (Em) values calculated based on the American Conference of Governmental Industrial Hygienists (ACGIH) and National Institute of Occupational Safety and Health (NIOSH) occupational exposure limits were higher than 1. Statistically significant increase of biochemical parameters (aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), total bilirubin, and direct bilirubin) was obtained in exposed workers of both genders compared with controls (p < 0.001). Calculated liver damage risk scores were significantly higher in both females and males compared with controls (p < 0.001). The multivariate logistic regression analysis showed that direct bilirubin was the most important predictor of organic solvent mixture exposure in the studied group of workers. These results suggest that combined exposure to organic solvents even at low concentrations may lead to hepatotoxicity.