Organophosphorous Pesticide Distribution in Seawater from Asan Bay, Korea in 2008

Abstract

: Distribution of organophosphorous pesticides (OPs) was studied from February to September 2008 in the seawater of Asan Bay, Korea. Among the 29 types of OPs detected during the study period, IBP(S-benzyl O,O-diisopropyl phosphorothioate), ranging from <1 ng/l to 377 ng/l, was the most abundant. Other commonly observed OPs concentrations in the study area included diazinon (Diethyl 2-isopropyl-4-methyl-6-pyrimidinyl phosphorothionate; <1~307 ng/l), azinphos ethyl (3,4-Dihydro-4-oxo-3-benzotriazinylmethyl O,O-diethyl phosphorodithioate; <1~1997 ng/l), malathion (1,2-Di(ethoxycarbonyl)ethyl O,Odimethyl phosphordithioates; <1~3013 ng/l), demeton-O (Diethyl 2-(ethylthio)ethyl phosphorothionate; <1~2403 ng/l), and DDVP (2,2-dichlorovinyl dimethyl phosphate; <1~283 ng/l). Seasonal distribution of OPs in seawater is dependent on the OP application period. In August, OPs concentrations were generally decreased with the increased salinity of seawater, implying progressive dilution of pesticides in the estuarine system. OPs were deposited into Asan Bay from Asan and Sabkyo Lakes as well as surrounding tributaries. Ten OPs, including diazinon, were detected in the suspended particles of Asan Bay.

Status of Pesticide Usage on Golf Courses in Korea and Optimal Pesticide Usage Plan

“…This value decreased slightly in 2015 and 2017, likely because of complex influences from natural environmental factors (such as precipitation) and socioeconomic factors (such as efforts to decrease pesticide usage). Because diseases and insect pests in turfgrass and trees in golf course areas were highly related to humidity, precipitation considerably affected the quantity of pesticides used [24]. According to the data obtained from the Korea Meteorological Administration (https://www.weather.go.kr, accessed on 22 December 2021), precipitation values in summer and autumn in 2014 and 2016 were 892.9 and 827.8 mm, respectively, which reduced to 634.8 and 782.2 mm in 2015 and 2017, respectively.…”

“…Out of the total quantity of pesticides used, the proportion of fungicide usage increased in the order of 56.6% → 61.1% → 65.7% → 65.8% → 67.2% in 2015-2019, respectively. Recently, the use of insecticides has decreased (35,36,27,32, and 31 tons in 2015-2019, respectively), and herbicide usage has showed a slightly changing trend (24,25,26,22, and 24 tons in 2015-2019, respectively). More than half the pesticides used on golf courses comprise fungicides, and their proportion is increasing; moreover, fungicides and insecticides account for most of them.…”