Nitrate and perchlorate contamination assessment using water samples for bioremediation behavior of nitrate ion with denitrifying bacteria and hypothyroidism of perchlorate ion in rat studies

Abstract

Perchlorate and nitrate ions are ubiquitous contaminants in the environment released from various activities which is increasingly affected the water quality and consequently the public health and agriculture. The denitrifying bacterial communities are potential drivers of water quality, soil fertility and agriculture productivity. The present study mainly assessed the contamination level of nitrate ion along with perchlorate ions in various water samples collected from fireworks, safety matches manufacturing industry areas around Pullalakkottai, Virudhunagar District, India. Nitrate, perchlorate, calcium, magnesium, sodium, potassium ions in water samples were qualitative and quantitatively analyzed by using various Physico-chemical analytical techniques. The observed maximum contamination values of nitrate and perchlorate ions were found to be 61 mg/L (VP-5), 85.5 mg/L (VP-11) respectively. The highly contaminated five water samples were subjected into bioremediation behavior of nitrate ion using the Pseudomonas sp., Bacillus sp. and Corynebacterium sp. bacterial cultures. The highest nitrate removal efficiency (E) 93.4 % was obtained with Corynebacterium sp. than the Bacillus sp. (83.6 %) and Pseudomonas sp. (80.3 %) cultured in contaminated water sample VP-3. Maximum perchlorate ions contaminated water samples (VP-11) used to examine the hypothyroidism in rat by intravenousinjection of observed days by measuring the T4 hormones level in the blood plasma. It was reduced to nearly half (296 µg/dl) in compared with control (620 µg/dl) for ten days exposure and notable decreasing trend was observed. Disruption of the thyroid can result in developmental disabilities and impair development especially among infants and children.