Mercury causes malformations to crabs of the Bay of Cispatá
UN/DICYT A UNal research project identified malformations in 70% of the analyzed crustaceans of the Bay of Cispatá (Province of Sucre), caused by increased levels of mercury in the water of the Sinú River. The research project developed jointly with the Universidad de Córdoba, discovered that this issue has produced crustacean malformations due to the pollutants in the Bay, particularly from mercury used in gold mining of the region. The Bay of Cispatá is located south of the Gulf of Morrosquillo, in the Province of Córdoba.
UNal-Caribbean Professor and Crustacean Specialist Researcher Néstor Hernando Campos discovered these malformations impact 70% of the crustaceans.
These crabs belong to the Goneplacidae and Xanthidea families, some are consumed by humans, such as the coral crab and others are small 2 to 3 cms (0.7 -1.1 in.) wide.
“Most part of the issue is teratogenic, in other words, able to disturb growth and development of crustacean larvae. This is produced by pesticides, high-density hydrocarbons and mercury dumped into the Sinú River, which ultimately pours into the Bay of Cispatá,” said Campos.
Most organic pollutants have mutagenic effects that produce morphologic alternations during embryo development as well as having carcinogenic effects.
According to Campos, mercury is an organic pollutant, and builds up in adipose tissue and turns into a venom which impacts several nervous cells.
“For crustaceans of the Gulf of Morrosquillo, the malformations come in different forms such as in crustacean bilateralism, manifested as different amount of thorns on each side of the body; there is also high incidence of diseases produced by bacteria that eat up their shells,” said Campos.
During the project, researchers took four samplings that belonged to different climatic seasons. Most malformations were discovered during the first season, i.e. during the first rain season between June and July.
This shows a direct effect between the amount of rain that enters the Sinú River and the discharge flow into the Bay of Cispatá.
From Japan to Cispatá
A similar case happened in Minamata (Japan) in the 1970s when the diseased was caused by organic mercury waste dumped by acetaldehyde and vinyl chloride plants.
Fish then began to accumulate these substances in their organisms producing a phenomenon known as bioamplification, in other words, concentration of a substance in the organism exceeds the background concentration of the substance in its diet.
The accumulation of organic mercury in Minamata trophic chains reached humans causing high mortality and genetic malformation rates in newborns as a consequence of fish consumption.
Professor Campos is also Director of UNal-Caribbean Ocean Sciences Research Center (CECIMAR, for its Spanish acronym) and Coordinator of the “IV Symposium on Ocean Sciences” recently held in UNal-Bogotá.