Pesticide monitoring in the Douglas-Daly region during the 2014 and 2015 Dry Seasons.
Details:
Title
Pesticide monitoring in the Douglas-Daly region during the 2014 and 2015 Dry Seasons.,
Creator
Schult, Julia,
Northern Territory. Department of Environment and Natural Resources,
Collection
E-Publications,
E-Books,
PublicationNT,
5/2016,
Date
2016,
Location
Douglas-Daly Region,
Description
Seven sites in the Douglas-Daly and lower Daly region were investigated for pesticide and herbicide contamination in the dry seasons of 2014 and 2015, when flows in the streams are supplied by groundwater. Two sites were situated on the middle and lower Daly River, two sites on the upper and lower Douglas River, and one site each on Stray Creek, Hayes Creek
and Green Ant Creek (Figure 1). Passive samplers were deployed in the streams for one month from August to September 2014 and September to October 2015 (lower Daly only) to detect trace levels of anthropogenic chemicals.
Pesticide and herbicide contamination of the streams was very low. Of 122 chemicals tested only 12 substances were found in the streams. Nine of these were herbicides and herbicide derivatives, one pesticide, the insect repellent DEET and a fragrance used in personal care products. Between 2 and 9 compounds were detected at any one site. The most commonly detected substances were herbicides of the triazine group (atrazine and simazine) that are highly water soluble and are known to have a high risk of leaching into groundwater. The herbicide atrazine or one of its break-down products was detected at all sites, while simazine
was found at 5 of the seven sites.
The concentrations of all the detected chemicals were very low and none exceeded ANZECC guidelines for the protection of slightly to moderately disturbed ecosystems.
However, the detection of any pesticides and herbicides serves to highlight that the use of these chemicals should meet best practice to minimise environmental contamination.,
Notes
Made available via the Publications (Legal Deposit) Act 2004 (NT).,