Tracing the attenuation of fipronil and its transformation products from a rice paddy field to receiving rivers using polar organic chemical integrative samplers.

Irrational use of fipronil for rice pest control often occurred, resulting in high concentrations of fipronil and its transformation products (TPs) (collectively termed fiproles) in aquatic sediment, calling for a better understanding of the migration and transformation of fipronil in surface water as well as efficient methods for source identification. Herein, the fate and transport of fiproles from a paddy field to receiving rivers were assessed in Poyang Lake basin, Jiangxi, China using polar organic chemical integrative samplers with mixed-mode adsorbents (POCIS-MMA). Average concentrations of fiproles in water were 6.

Occurrence and water-sediment exchange of systemic insecticides and their transformation products in an agriculture-dominated basin.

Neonicotinoids (NEOs) and fipronil (FIP) are ubiquitous in aquatic environment, yet the transformation and water-sediment exchange are largely unknown for these systemic insecticides and their transformation products (TPs). Herein, occurrence, field-based partitioning coefficients, and fugacity fractions (ff) of NEOs, FIP, and their TPs were analyzed in the drainage and receiving rivers near a rice paddy field. NEOs and FIPs were frequently detected in the sediments with concentrations of TPs being often higher than the parent compounds.

Spatial distribution of benthic toxicity and sediment-bound metals and arsenic in Guangzhou urban waterways: Influence of land use.

The effects of land use on pollutant loads in sediments have been well documented; however, its influence on spatial variations in sediment toxicity remains largely unknown. In the present study, the toxicological effects of 17 sediments collected from Guangzhou waterways were evaluated using two benthic invertebrates (Chironomus dilutus and Hyalella azteca), along with quantification of heavy metals and arsenic in the sediments. The impacts of land-use configuration on sediment toxicity and occurrence of heavy metals and arsenic were analyzed.