Abstract

Snail's embryotoxicity test is a suitable approach for toxicity assay of traditional and emerging pollutants, environmental risk assessment, as well 3️⃣ as screening and development of new molluscicides. Among the snail species, Biomphalaria spp. has been indicated as a promising model 3️⃣ system for developing standardized test protocols for assessing the chemical toxicity using early developmental stages. Thus, the current study aimed 3️⃣ to review the data available in the scientific literature concerning the experimental approach, type of chemicals and the response of 3️⃣ multiple biomarkers (survival, hatching rate, development delays, morphological and behavior changes) in snail embryos applied in toxicity tests. Revised data 3️⃣ showed that the use of Biomphalaria embryos to assess chemical toxicity began in 1962. Snail's embryotoxicity test was applied mainly 3️⃣ for analyzing the toxicity and development of new molluscicides, while its use in ecotoxicological studies is emerging. Biomphalaria glabrata was 3️⃣ the main species analyzed. Embryos exposed to chemicals showed bioaccumulation, mortality, hatching inhibition, development delays, and morphological malformations, which were 3️⃣ classified into four categories (hydropic, shell, cephalic and unspecified malformations). Besides, research gaps and recommendations for future research are indicated. 3️⃣ Overall, the results showed that the Biomphalaria embryotoxicity test (BET) is a suitable tool for toxicity and health risk assessment.