In the current study, Persistent Organic Pollutants (POPs) in outdoor dustfall was monitored for the first time along the Indus river system of Pakistan. Among the studied OCPs (ng/g, dry weight), DDTs (0.16–62) were the predominant contaminants identified in deposited dust followed by HCHs (0.1–10.2), HCB (0.09–7.4) and chlordanes (0.1–2.8). The indicative diagnostic ratio for DDTs and HCHs suggested recent emission of DDTs as well as historical emission of both chemicals in regions where they were used for crop protection and malarial control. The levels of ∑31PCBs (ng/g, dry weight) in dust ranged from 0.95–125, and compositional profiles suggested arochlor-1248, -1254 commercial mixtures as source. A few exceptions were samples from urban areas that reflected the use of aroclor-1260, and-1262 and/or unintentional leakage from several industrial processes. The WHO05-TEQ values for dioxin-like PCBs (with major contributions of PCB-126) were found to be 0.07–34.5 (median; 1.87) pg TEQ g− 1dw for all the studied samples. Correlation analysis identified that DDTs, HCHs, HCB and PCBs were significantly associated (r = 90; p < 0.01) with dusts collected in proximity to urban centers with widespread anthropogenic activities in these areas. A few cases where high levels of POPs from remote mountain highlands were detected, point to the potential for long range transport of these chemicals. Human risk assessment analysis of contaminated dust showed that DDTs and PCBs are major constituent chemicals of concern with regard to the development of cancer in children, with ingestion being the main route of exposure of dust-borne DDTs (0.12–1.03 × 10− 6) and PCBs (0.86–12.43 × 10− 6).
General news | 2018-03-19
In 2017, we surpassed one thousand published articles in peer-reviewed journals and we hosted the fourth international conference on resilience and sustainability science. Another year to be proud of, we think
Research news | 2018-03-14
Amid an increase in megacities, changes in ecosystems far away can affect local access to freshwater
Research news | 2018-03-12
Ten essentials for guiding action-oriented research on energy transformation and climate change
Research news | 2018-03-09
To celebrate International Women’s Day, we have been highlighting some of our women researchers at the centre. In our final profile this week, we showcase associate professor Beatrice Crona, whose work spans from small-scale fisheries governance to global drivers of change.
Research news | 2018-03-08
To celebrate International Women’s Day, we are highlighting some of our women researchers. We would now like to showcase Jennifer Hinton, a PhD candidate studying the social dynamics of a sustainable biophysical resource economy
Research news | 2018-03-08
New method to map livelihood benefits of ecosystem services for guiding future land use decisions in the Sahel