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Industrial water contamination and health impacts: an economic perspective

100%

Sayal A. , Amjad S. , Bilal M. , Pervez A. , Mahmood Q. , Afridi M. A.

nr 2

The present study quantifi ed and evaluated the presence of water pollution and its impact on the health of the adjacent human community. Water sampling and household surveying was carried out using a GIS approach using primary data. The quantifi cation of health impact was based on the scientifi c tools of environment, economic theory, econometrics, and statistics. The focus of our study was the impact of lead (Pb) contamination of drinking water from industrial effl uents on population health and utility in Dingi village, adjacent to an industrial estate in Haripur Pakistan. Results of the study showed varying Pb contamination beyond the safe limits set by WHO. Marginal willingness to pay based on probabilities of sickness, medical costs, and avertive costs was estimated at $53 per household yearly. The opportunity cost of leisure ($22) and avertive measures ($54) were also estimated to fi nd the total economic cost born by households ($300). Total annual welfare loss of the Dingi community exposed to Pb contamination and its cost accounted for 4.26 million PKR ($42,000). This welfare quantifi cation extrapolated to other villages can contribute to heavy monetary loss. Policymakers should pay special attention to such polluted areas to adopt mitigation measures to save public health.

Novel lignocellulosic wastes for comparative adsorption of Cr(VI): equilibrium kinetics and thermodynamic studies

100%

Haroon H. , Gardazi S. M. H. , Butt T. A. , Pervez A. , Mahmood Q. , Bilal M.

tom Vol. 19, nr 2

6--15

Cr(VI) adsorption was studied for abundantly available low-cost lignocellulosic adsorbents in Pakistan namely, tobacco stalks (TS), white cedar stem (WCS) and eucalyptus bark (EB). Several process variables like contact time, adsorbent dose, pH, metal concentration, particle size and temperature were optimized in batch mode. EB showed high Cr(VI) adsorption of 63.66% followed by WCS 62% and TS 57% at pH 2, which is higher than most of the reported literature. Langmuir isotherm (R2 = 0.999) was well fitted into the equilibrium Cr(VI) data of EB, suggesting homogeneous active sites and monolayer coverage of Cr(VI) onto the EB surface. Freundlich (R2 = 0.9982) isotherm was better fitted to the equilibrium data of TS and WCS, revealing the adsorption sites with heterogeneous energy distribution and multilayer Cr(VI) adsorption. Moreover, the Cr(VI) adsorption of studied adsorbents followed the pseudo-second order kinetic model. Thermodynamic properties were investigated in two temperature ranges, i.e., T1 (303–313 K) and T2 (313–323 K). TS and EB showed the exothermic at T1 and endothermic reactions at T2 with entropy controlled adsorption at the solid-liquid interface, and WCS exhibited an opposite thermal trend with decreasing disorderness at solid-liquid interface as temperature rises. Gibbs free energy (ΔG>0) confirmed the non-spontaneous adsorption process for all studied adsorbents.