Evaluation of Chemcatcher® passive samplers for pesticide monitoring using high-frequency catchment scale data

Luke G Farrow; Phoebe A Morton; Rachel Cassidy; Stewart Floyd; W Colin McRoberts; Donnacha G Doody; Philip Jordan

doi:10.1016/j.jenvman.2022.116292

Evaluation of Chemcatcher® passive samplers for pesticide monitoring using high-frequency catchment scale data

J Environ Manage. 2022 Dec 15:324:116292. doi: 10.1016/j.jenvman.2022.116292. Epub 2022 Sep 30.

Authors

Luke G Farrow¹, Phoebe A Morton², Rachel Cassidy³, Stewart Floyd⁴, W Colin McRoberts⁵, Donnacha G Doody⁶, Philip Jordan⁷

Affiliations

¹ Agri-Environment Branch, Agri-Food and Bioscience Institute, Belfast, UK. Electronic address: Luke.farrow@afbini.gov.uk.
² Agri-Environment Branch, Agri-Food and Bioscience Institute, Belfast, UK. Electronic address: Phoebe.morton@afbini.gov.uk.
³ Agri-Environment Branch, Agri-Food and Bioscience Institute, Belfast, UK. Electronic address: Rachel.cassidy@afbini.gov.uk.
⁴ Food Research Branch, Agri-Food and Bioscience Institute, Belfast, UK. Electronic address: Stewart.floyd@afbini.gov.uk.
⁵ Food Research Branch, Agri-Food and Bioscience Institute, Belfast, UK. Electronic address: Colin.McRoberts@afbini.gov.uk.
⁶ Agri-Environment Branch, Agri-Food and Bioscience Institute, Belfast, UK. Electronic address: Donnacha.doody@afbini.gov.uk.
⁷ School of Geography and Environmental Sciences, Ulster University, Coleraine, UK. Electronic address: P.jordan@ulster.ac.uk.

Abstract

Passive samplers (PS) have been proposed as an enhanced water quality monitoring solution in rivers, but their performance against high-frequency data over the longer term has not been widely explored. This study compared the performance of Chemcatcher® passive sampling (PS) devices with high-frequency sampling (HFS: 7-hourly to daily) in two dynamic rivers over 16 months. The evaluation was based on the acid herbicides MCPA (2-methyl-4-chlorophenoxyacetic acid), mecoprop-P, fluroxypyr and triclopyr. The impact of river discharge parameters on Chemcatcher® device performance was also explored. Mixed effects modelling showed that time-weighted mean concentration (TWMC) and flow-weighted mean concentration (FWMC) values obtained by the HFS approach were both significantly higher (p < 0.001) than TWMC values determined from PS regardless of river or pesticide. Modelling also showed that TWMC_PS values were more similar to TWMC_HFS than FWMC_HFS values. However, further testing revealed that MCPA TWMC values from HFS and PS were not significantly different (p > 0.05). There was little indication that river flow parameters altered PS performance-some minor effects were not significant or consistent. Despite this, the PS recovery of very low concentrations indicated that Chemcatcher® devices may be used to evaluate the presence/absence and magnitude of acid herbicides in hydrologically dynamic rivers in synoptic type surveys where space and time coverage is required. However, a period of calibration of the devices in each river would be necessary if they were intended to provide a quantitative review of pesticide concentration as compared with HFS approaches.

Keywords: Acid herbicides; Catchment-scale; Chemcatchers®; High frequency sampling; Passive sampling; Water quality monitoring.

MeSH terms

2-Methyl-4-chlorophenoxyacetic Acid*
Environmental Monitoring
Herbicides*
Pesticides* / analysis
Rivers
Water Pollutants, Chemical* / analysis

Substances

Pesticides
2-Methyl-4-chlorophenoxyacetic Acid
Water Pollutants, Chemical
Herbicides