Impacts of Tannery Effluent on Environments and Human Health: A Review Article

Abstract

Tannery industry is a primary pollutant of the environment and has a strong potential to cause soil and water pollution owing to the discharge of untreated effluent. It uses more than 250 chemicals for leather production and release a complex mixture of toxic organic chlorinated phenols, toxic Cr(VI), and other toxic pollutants such as sulphides, phenolic compounds, magnesium, sodium, potassium, azo-dyes, cadmium compounds, cobalt, copper, antimony, barium, lead, selenium, mercury, zinc, arsenic, PCB, nickel, formaldehyde resins, pesticides residues, mineral salts, dyes and solvents like grease and oils. Cr(VI) and chlorinated phenols are the basic prominent sewage toxic to biota and humans as well as other environments or ecosystems. Based on different researchers on different countries and different environmental samples like soils, waters, and vegetables in almost all (more than 99.99%) of Cr(VI) is above the permissible limit of WHO, FAO, EPA, and other countries maximum discharging and existing limits. Cr(VI) have different health effects and cause for acute toxicity, mutagenic, carcinogenic and high blood pressure for societies used untreated waste water contain large amount of Cr(VI) discharged from any tannery industries and also affect seed germination of the plants. The levels of Cr(VI) in the downstream river and spring water samples exceed from WHO permissible limit of total chromium in drinking waters (0.05 mg/L). The increased concentration of Cr(VI) in the water samples indicate the possible environmental pollution of downstream water bodies by the tannery effluent, soil and vegetables.

Keywords: Tannery, Effluents, Environments, Hexavalent Chromium