Hazard assessment of metals in invasive fish species of the Yamuna River, India in relation to bioaccumulation factor and exposure concentration for human health implications.

Monitoring of heavy metals was conducted in the Yamuna River considering bioaccumulation factor, exposure concentration, and human health implications which showed contamination levels of copper (Cu), lead (Pb), nickel (Ni), and chromium (Cr) and their dispersion patterns along the river. Largest concentration of Pb in river water was 392 µg L(-1); Cu was 392 µg L(-1) at the extreme downstream, Allahabad and Ni was 146 µg L(-1) at midstream, Agra. Largest concentration of Cu was 617 µg kg(-1), Ni 1,621 µg kg(-1) at midstream while Pb was 1,214 µg kg(-1) at Allahabad in surface sediment. The bioconcentration of Cu, Pb, Ni, and Cr was observed where the largest accumulation of Pb was 2.29 µg kg(-1) in Oreochromis niloticus and 1.55 µg kg(-1) in Cyprinus carpio invaded at Allahabad while largest concentration of Ni was 174 µg kg(-1) in O. niloticus and 124 µg kg(-1) in C. carpio in the midstream of the river. The calculated values of hazard index (HI) for Pb was found more than one which indicated human health concern. Carcinogenic risk value for Ni was again high i.e., 17.02 × 10(-4) which was larger than all other metals studied. The results of this study indicated bioconcentration in fish due to their exposures to heavy metals from different routes which had human health risk implications. Thus, regular environmental monitoring of heavy metal contamination in fish is advocated for assessing food safety since health risk may be associated with the consumption of fish contaminated through exposure to a degraded environment.

Polycyclic aromatic hydrocarbons and their quinones modulate the metabolic profile and induce DNA damage in human alveolar and bronchiolar cells.

The release of particulate pollutants into the air through burning of coal, crude oil, diesel, coal tar, etc. raises concerns of potential health hazards to the exposed human population. Polycyclic aromatic hydrocarbons (PAHs) are major toxic constituents of particulate matter (PM), which upon ingestion get metabolized to even more toxic metabolites such as quinones. The PAHs levels were assessed in both respirable particulate matter (RSPM, <10µM size) and suspended particulate matter (SPM, >10µM size) of urban ambient air (UAA) and that of major contributors viz. diesel exhaust particles (DEPs) and coal tar combustions emissions (CTCE). Seven US Environmental Protection Agency (USEPA) prioritized PAHs in RSPM and 10 in SPM were detected in UAA. Ten and 15 prioritized PAHs, respectively, were also detected in diesel exhaust particles (DEP) and coal tar combustion emission (CTCE) evidencing their release in the air. These PM associated PAHs for UAA, DEP and CTCE showed significant increase (p<0.05) in mutagenicity and mammalian genotoxicity in the order CTCE>DEP>UAA. Human lung alveolar (A549) and bronchiolar (BEAS-2B) cells when treated with PAH-metabolites viz. 1,4-benzoquinone (1,4-BQ), hydroquinone (HQ), 1,2-naphthoquinone (1,2-NQ), 1,4-naphthoquinone (1,4-NQ) and 9,10-phenanthroquinone (9,10-PQ) showed metabolic modulation in these cell lines with significant depletion of principal cellular metabolites viz. NADP, uracil, asparagines, glutamine, and histidine and accumulation of di-methyl amine and beta-hydroxybutyrate, identified using (1)H NMR spectroscopy. These results suggest that PAH-quinones induce genotoxic effects by modulating the metabolic machinery inside the cells by a combined effect of oxidative stress and energy depletion. Our data for metabolic profiling of human lung cells could also help in understanding the mechanism of toxicity of other xenobiotics.

Seasonal trends of PM2.5 and PM10 in ambient air and their correlation in ambient air of Lucknow city, India.

The PM(10) concentration (µg/m(3)) in Lucknow city at 4 locations in three different seasons ranged between 148.6-210.8 (avg. 187.2 ± 17.1) during summer, 111.8-187.6 (avg. 155.7 ± 22.7) during monsoon and 199.3-308.8 (avg. 269.3 ± 42.9) during winter while PM(2.5) ranged between 32.4-67.2 (avg. 45.6 ± 10.9), 25.6-68.9 (avg. 39.8 ± 4.6) and 99.3-299.3 (avg. 212.4 ± 55.0) during respective seasons. The mass fraction ratio of PM(2.5) ranged between 0.22-0.92 (avg. 0.42 ± 0.26) and was significantly high during winter season indicating their composition.