Water Pollution Simulation and Health Risk Assessment Through a Refined Contaminant Transport Model

Abstract

To address the growing concerns on water pollution caused by pesticide losses, this study aimed at refining a contaminant transport model and applying it to health risk assessment for pesticidecontaminated water. It was an advance of the previous modeling works by integrating a dynamic two-bigleaf multilayer pesticide emission module with the existing pesticide runoff loss simulation model (PeLM). A risk assessment approach was further employed to evaluate the health effects based on the simulation of pesticide pollution by the refined model. The modeling performance and feasibility were examined through a case study conducted in the AuglaizeBlanchard Watershed, OH, USA. A widely used herbicide, atrazine, was targeted. Both the original and refined PeLM were tested and compared. The results indicated that the refined model had advantages in accounting for more pesticide transport processes and improving the simulation accuracy. The risk assessment results disclosed that atrazine concentrations in the river were usually lower than the American standards. To further explore the potential pesticide pollution problems and the associated health risks, a more stringent standard (i.e., Canadian guideline) was also employed. The results indicated that the daily average concentrations of the pesticide sometimes markedly surpassed the guideline, particularly during the wet season (May to August). Correspondingly, the maximum values of the chronic and acute hazard indices could exceed over 1.3 times of the recommended thresholds. The developed methodologies and findings would help raise concerns on pesticide pollution and provide support for decision making related to water pollution mitigation and quality management.

Influência Da Taxa De Dose Potencial Variável Em Áreas Contaminadas No Cálculo Do Risco À Saúde Humana

“…A partir das concentrações simuladas, pode-se calcular a dose anual e/ou risco anual radiológico como uma função do tempo, e comparar os resultados obtidos temporalmente com os limites estabelecidos pelas legislações (IAEA, 1999;CNEN, 2005;PONTEDEIRO et al, 2007PONTEDEIRO et al, , 2010. Sob a mesma ótica utilizada na análise de risco de rejeitos radioativos, alguns estudos têm aprofundado a influência da temporalidade das concentrações na toxicidade e no risco de substâncias químicas ambientais (BIÉN et al, 2004;CHEN, 2009;BACIOCCHI et al, 2010;ANDRICEVIC et al, 2012). O objetivo deste trabalho é apresentar um estudo de caso de um experimento de campo com liberação controlada de gasolina brasileira (contendo 24% de etanol) e monitorado durante 14 anos (CORSEUIL et al, 2011) para avaliar a influência da temporalidade na quantificação do risco à saúde humana, considerando a variação das concentrações dos contaminantes desde a sua liberação na água subterrânea até a sua completa atenuação.…”

Field Investigation and Hydrological Modelling of a Subarctic Wetland - the Deer River Watershed

“…To help better understand and predict the water cycle, hydrological modelling has been playing a significant role in studying the distinguished attributes of subarctic wetlands. Numerous models have been developed and applied for hydrology simulation, such as hydrologic engineering center (HEC-1), semidistributed land use-based runoff process (SLURP), precipitation-runoff modelling system (PRMS), streamflow synthesis and reservoir regulation (SSARR), snowmelt runoff model (SRM), UBC, WATFLOOD, and TOPMODEL (Quick and Pipes, 1977;Beven et al, 1984;Abbott et al, 1986;Bergström, 1992;Kouwen et al, 1993;Bicknell et al, 1997;Kite, 1997;Richard and Gratton, 2001;Chen et al, 2003Chen et al, , 2004Chen et al, , 2007Chen et al, , 2008. However, only a few studies specifically targeted at subarctic wetlands, particularly the HBL in northern Manitoba due to a number of knowledge gaps, such as the difficulty of considering continuous permafrost, numerous seasonal ponds, and snow sublimation as well as the complexity of simulating water linkage between surface and subsurface flows in the hummocky terrain (Mancell et al, 2000;Zhang et al, 2000;Van der Linden and Woo, 2003;Boswell and Olyphant, 2007).…”

“…Maximum, Minimum and Mean of Annual Cumulative Precipitation (P cum ) and Annual Average Air Temperature (T avg ) over a 31-year Period at the Churchill Airport(1978-2008 …”