Human Exposures to Neonicotinoids in Kumasi, Ghana

• Published in: Environmental toxicology and chemistry 2021-08, Vol.40 (8), p.2306-2318
• Main Authors: Nimako, Collins, Ikenaka, Yoshinori, Akoto, Osei, Bortey‐Sam, Nesta, Ichise, Takahiro, Nakayama, Shouta M.M., Asante, Kwadwo A., Fujioka, Kazutoshi, Taira, Kumiko, Ishizuka, Mayumi
• Format: Article
• Language: English
• Subjects: Acetic acid; Biomonitoring; Chronic reference dose; Exposure; Farming systems; Female; Ghana; Humans; Imidacloprid; Imidacloprid equivalent; Insecticides; Insecticides - analysis; Ionization; Ions; Liquid chromatography; Male; Mass spectrometry; Mass spectroscopy; Metabolites; Neonicotinoid; Neonicotinoids - analysis; Nitro Compounds; Pesticide risk assessment; Pesticides; Thiacloprid; Thiamethoxam
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.5065

Neonicotinoid insecticides (NNIs) are now popular in many agricultural systems across Africa; however, the extent of human exposures to NNIs in African countries is scarcely reported. The present study evaluates neonicotinoid exposures in the consumer population of Kumasi, a cosmopolitan city in Ghana. A total of 75 human urine samples were collected from healthy volunteers (nonfarmers, aged 13–80 yr) and analyzed with a liquid chromatography electrospray ionization tandem mass spectrometry system. Seven NNIs and 3 NNI metabolites were detected in the following pattern (frequency, median concentration, maximum concentration): N‐dm‐acetamiprid (94.7%, 0.41 µg/L, 8.79 µg/L) > imidacloprid (70.7%, 0.15 µg/L, 211.62 µg/L) > N‐(6‐chloro‐3‐pyridylmethyl)‐N‐ethyl‐N′‐methylformamidine (62.2%, 0.43 µg/L, 53.85 µg/L) > 2‐[N‐(6‐chloro‐3‐pyridylmethyl)‐N‐ethylamino]‐2‐(methylimino)acetic acid (56.8%, 0.10 µg/L, 3.53 µg/L) > clothianidin (40%, >limit of quantification [LOQ], 0.45 µg/L) > nitenpyram (18.7%, >LOQ, 0.14 µg/L) ≈ thiamethoxam (18.7%, >LOQ, 0.21 µg/L) > dinotefuran (12.0%, >LOQ, 1.01 µg/L) > acetamiprid (2.7%, >LOQ, 0.08 µg/L) ≈ thiacloprid (2.7%, >LOQ, 0.14 µg/L). Approximately 92% of the subjects were found to be exposed to multiple neonicotinoids simultaneously. The mean, median, and maximum imidacloprid equivalent of the relative potency factor of NNIs were found to be 1.6, 0.5, and 22.52, respectively. The median estimated daily intakes of acetamiprid, imidacloprid, and nitenpyram were 0.47, 1.27, and 0.02 µg/kg/d for females and 0.91, 0.66, and 0.08 µg/kg/d for males, respectively. The maximum daily intakes of all the NNIs were