Algal-bacterial intervention as a management tool for next-generation aquaculture sustainability

Abstract

Emerging occupational and environmental health problems are currently major priorities that need to be tackled along with existing traditional public health problems like communicable diseases, malnutrition, poor environmental sanitation, and inadequate medical facilities. Although toxicologists have expressed deep concern and have prioritized these issues, public awareness, toxicological databases, suitable early diagnosis, specific preventive and therapeutic measures are some of the major issues which requires major attention. Among various strategies which may address these issues include use of modern technologies, amenities, and resources for detecting toxic substances or their derivatives at nanogram (ng) levels.These steps will be important to specifically quantify various toxicants and facilitate future research in order to (i) safe and specific therapeutic or preventive measures and (ii) early diagnosis/ biomarkers to examine effects at the molecular level. It has recently been realized that most of the diseases related to toxicants are incurable; therefore, the best course of action in dealing with them is prevention (Flora, 2008). Heavy metal induced toxicity and its associated complications have become a major issue in the medical world. Heavy metals accumulation in the environment and their associated health hazards still need to be extensively studied as there are many unanswered questions like early diagnosis and specific treatment particularly in case of chronic exposure. Exposure to heavy metals (like lead, cadmium and mercury) or metalloids like arsenic come from a variety of sources, including gasoline, fertilizers, paints, sewage sludge, ground water, wastewater irrigation, pesticides, coal burning residues, domestic and industrial effluents, and petrochemicals. Heavy metals are characteristic representatives of toxic substances which are not biodegradable, enter the food chain, and accumulate in living systems. Increased concentrations and accumulation of Heavy metals can cause severely damaging effects and associated complications in living organisms and can even lead to the death of the organism. Heavy metals toxicity generally lessens energy levels and can severely damage and decrease the function of the brain, kidney, lungs, and liver. Frequent and continuous exposure to heavy metals or metalloids leads to physical, muscular, and neurological degeneration, emulating disorders such as Parkinson's disease, Alzheimer's disease, Wilson's disease, muscular dystrophy, and multiple sclerosis etc. Exposure to lead toxicity causes ionic and oxidative stress conditions in living organisms, occurring due to an imbalance in free radical production and antioxidant levels which normally neutralize or detoxify the reactive intermediates. Antioxidants can protect against free radical mediated damage, providing its reducing equivalents from sulphur groups of cysteine to reactive oxygen species (ROS) and making them stable (Flora et al., 2013). Elevated levels of ROS damages the cells and cellular components, which results in a harassed condition at the cellular level. The ionic mechanism of lead or arsenic toxicity also causes substantial deviations in apoptosis, ionic transportation, cell adhesion, inter- and intra-cellular signalling, protein folding and maturation, the release of neurotransmitters, and enzyme regulation (Pachauri et al., 2013).