**6. Conclusions**

The use of invertebrates as bioindicators to assess environmental risks occupies a high priority for researchers and environmental observers due to their efficient and rapid responses to various external causes. However, toxic elements are capable of penetrating the body and accumulating in certain tissues, causing cellular alterations as well as damage to energy metabolism, growth and reproduction. Further study of the issue would be of interest to improve international guidelines for metal pollutants and to develop maintenance plans to protect invertebrates and ecosystem services.
