Abstract

Snail's embryotoxicity test is a suitable approach for toxicity assay of traditional and emerging pollutants, environmental risk assessment, as well 7️⃣ as screening and development of new molluscicides. Among the snail species, Biomphalaria spp. has been indicated as a promising model 7️⃣ system for developing standardized test protocols for assessing the chemical toxicity using early developmental stages. Thus, the current study aimed 7️⃣ to review the data available in the scientific literature concerning the experimental approach, type of chemicals and the response of 7️⃣ multiple biomarkers (survival, hatching rate, development delays, morphological and behavior changes) in snail embryos applied in toxicity tests. Revised data 7️⃣ showed that the use of Biomphalaria embryos to assess chemical toxicity began in 1962. Snail's embryotoxicity test was applied mainly 7️⃣ for analyzing the toxicity and development of new molluscicides, while its use in ecotoxicological studies is emerging. Biomphalaria glabrata was 7️⃣ the main species analyzed. Embryos exposed to chemicals showed bioaccumulation, mortality, hatching inhibition, development delays, and morphological malformations, which were 7️⃣ classified into four categories (hydropic, shell, cephalic and unspecified malformations). Besides, research gaps and recommendations for future research are indicated. 7️⃣ Overall, the results showed that the Biomphalaria embryotoxicity test (BET) is a suitable tool for toxicity and health risk assessment.