Mercury Accumulation and Elimination in Different Tissues of Zebrafish (Danio rerio) Exposed to a Mercury-Supplemented Diet

Abstract

In this study, we evaluated the bioaccumulation of mercury in zebrafish (Danio rerio) exposed to mercury-contaminated food for 21 days and the depuration of mercury for a subsequent post-exposure period of 28 days. Four tissues (muscle, liver, gills, and skin) were analyzed for mercury content. Overall, data indicated that Hg accumulation in the liver is faster than in other tissues. Furthermore, the liver is the tissue with the highest accumulation rate per day (0.021 µg Hg g−1 day−1), followed by muscle, skin, and gills. Conversely, the Hg depuration rates in different tissues showed the following order: gills > skin > muscle > liver. The bioaccumulation factor values of liver and muscle increased linearly during the uptake period. The ratios between mercury concentration in liver and muscle during the experiment also increased during the uptake period and remained higher than 1 during the elimination period, suggesting that Danio rerio needed more than 4 weeks of depuration. Finally, the distribution of Hg in the water column during the accumulation period is Hg particulate > Hg dissolved, and during the depuration period it is the opposite, mercury particulate < mercury dissolved. In conclusion, this study contributes to a better understanding of the differences in Hg dynamics during the accumulation and depuration stages in a model fish, also emphasizing the alterations on Hg available in the water column.

Maternal provisioning interacts with incubation temperature to affect hatchling mercury exposure in an oviparous reptile

“…The second possibility is that depuration processes actively remove detoxified mercury from the liver, decreasing hepatic concentrations in the absence of additional inputs. Liver to muscle THg ratios can be used as indicators of active mercury uptake (ratios greater than 1) or depuration (ratios less than 1) [54,55,[63][64][65]. Incubation at FPT resulted in higher ratios compared to those observed in individuals incubated at MPT, suggesting that incubation temperature may alter mercury depuration rates in hatchling alligators, although future research is needed to experimentally verify this link.…”

A Retrospection on Mercury Contamination, Bioaccumulation, and Toxicity in Diverse Environments: Current Insights and Future Prospects

“…Fish muscle is the most examined tissue for Hg accumulations because it appears to operate as a Hg reservoir to protect other organs, and it is the major fish tissue ingested by humans. Hg also tends to concentrate in detoxifying organs like the liver and kidney [140]. For this, zebrafish (Danio rerio) were investigated with Hg-contaminated diet for 21 days and then monitored their Hg levels for another 28 days to determine bioaccumulation and depuration.…”

“…During the absorption phase, the liver showed the greatest accumulation rates because of its central role in detoxification. However, the time it took for Hg to be eliminated from the Danio rerio liver was shown [140].…”

A Simplified Approach to Modeling the Dispersion of Mercury from Precipitation to Surface Waters—The Bay of Kaštela Case Study

“…The reduction of oxidized Hg species can result in its (re)emissions to the atmosphere [1,3,4], while methylation creates the most toxic Hg species-monomethylmercury and dimethylmercury [5][6][7]. In general, all Hg species are considered to be chemicals of concern as they can cause adverse health effects in humans and animals through the consumption of contaminated food [8,9].…”