Changes in Acid Herbicide Concentrations in Urban Streams after a Cosmetic Pesticides Ban

Challenges

Aaron Todd¹ 

[1] Environmental Monitoring and Reporting Branch, Ontario Ministry of the Environment, 125 Resources Road, Toronto, ON M9P 3V6, Canada

关键词: acid herbicides;    surface water quality;    urban streams;    cosmetic pesticides ban;    pesticide use regulation;   

DOI  :  10.3390/challe5010138

来源: mdpi

【 摘 要 】

Surface water concentrations of the acid herbicides 2,4-D, dicamba and mecoprop were measured in ten urban Ontario streams before (2003–2008) and after (2009–2012) a ban on the sale and use of pesticides for cosmetic (non-essential) purposes. Frequencies of detection (2003–2012) were 98%, 96% and nearly 100%, respectively for 2,4-D, dicamba and mecoprop. Concentrations were typically in the ng L⁻¹ range, although periodic spikes in the µg L⁻¹ range were observed. Concentrations in a majority of the study streams decreased significantly following the cosmetic pesticides ban. Concentrations decreased from 16% to 92% depending on the stream and herbicide. The presence of these herbicides in urban streams was likely a result of urban applications. Concentrations were significantly related to population density or urban land cover, and the relative proportion of the three herbicides observed in urban stream water approximated the ratios found in pesticide products formulated for urban use. Longer-term trends indicate that decreases in stream water herbicide concentrations may have preceded the ban and may be related to increased public awareness of pesticide issues and voluntary reductions in urban pesticide use.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.