Transfer of organic ultraviolet absorbers consumed by laying hens to various tissues in newborn chicks.

Some exogenous organic pollutants can be accumulated in animals and subsequently be transferred to their offspring. However, the accumulation and maternal transfer characteristics of organic ultraviolet absorbers (OUVAs) in terrestrial species remain poorly understood. This study investigated the accumulation of six OUVAs in domestic hens and their eggs, as well as the subsequent maternal transfer behaviors. Following continuous oral exposure to OUVAs, the average concentration and clearance half-life (33.0 days) of UV-327 were found to be higher than those of the other chemicals in target tissues of hens. The concentration ratios of yolk-liver were 9.19, 5.21, and 5.12 for UV-326, UV-329 and UV-327, respectively, indicating that these chemicals were readily transferred to the eggs. Approximately 56.6%-82.2% of individual OUVAs in the yolk were absorbed by the chicken embryos during incubation, with UV-327 exhibiting the highest absorption rate. In newborn chicks, the three OUVAs, including UV-327, EHMC and 4-MBC, showed significant accumulation in the liver and brain, while the other chemicals primarily accumulated in the muscles. Our findings confirm the strong maternal transfer potential of these OUVAs in domestic hens and highlight concerns about their hram on specific tissues. Given similar habits and feeding ecology, these results also highlight potential implications for wild avian species.