Written by Chrystal Moulton, Staff Writer. A survey of urinary concentrations of neonicotinoid insecticides suggest widespread exposure among the Chinese population.
Neonicotinoids insecticides are formulated to target the nicotinoid acetylcholine receptors of common pests that attack crops. This includes aphids, white flies, and some insects within the coleopteran, dipteran and lepidopteran species 1. This class of insecticide is very effective and popular among farmers because of its low toxicity and inability to develop resistance 2. However, some research has linked neonicotinoids to decline in the diversity and distribution of the bee population 3, decline in insectivorous birds 4, and possible toxic effects in the neurological, hepatic, genetic, and reproductive systems in animals and humans 5. In the current study, researchers determined the urinary concentration of 6 neonicotinoid insecticides among the general population from 12 provinces in China 6. This information will provide a profile of the source and spatial distribution of various neonicotinoid insecticides (Neo insecticides) used in China and serve as a framework for understanding the human health risk linked to use these insecticides.
Urine samples were collected from 324 participants in 2016 and 2017 in urban and rural areas of China. Participants comprised of 195 males and 115 females aged 1 to 97 years old. Gender was not specified for 14 samples. Urine samples were assessed for 6 Neo insecticides: acetamiprid (ACE), thiacloprid (THD), clothianidin (CLO), imidacloprid (IMI), thiamethoxam (THM), and dinotefuran (DIN).
All six Neo insecticides were detected in the urine samples. Clothianidin (CLO) had the highest median concentration of 0.24 ng/mL, followed by imidacloprid (IMI) [0.21 ng/mL], thiamethoxan (THM) [0.15 ng/mL], and dinotefuran (DIN) [0.14 ng/mL]. Participants from GL-Guangxi province had the highest median urinary concentration of all six Neo insecticides at 3.9 ng/mL, followed by CF-Inner Mongolia (3.3 ng/mL), MM-Guangdong (2.1 ng/mL), NT-Jiangsu (2.0 ng/mL), DY-Shandong and DT-Shanxi (1.5 ng/mL). Higher urinary concentrations of Neo insecticides were generally found in the northern, southern, and eastern regions of China especially in coastal provinces. Regional distribution of the sum of Neo insecticide urinary concentration was consistent with the pattern of insecticide use nationwide. CLO accounted for 32% of the sum of urinary concentration of Neo insecticides followed by IMI at 28%, THM at 21%, DIN at 17%, Ace at 1.8%, and THD at 0.2%. Collectively, CLO, IMI, and THM accounted for 98% of the sum of urinary Neo insecticide concentration. In examining age-related patterns of urinary neo insecticide concentrations, no association was found. However, a significantly higher concentration of the sum of urinary Neo insecticides was found in men versus women (1.4 ng/mL vs. 0.98 ng/mL, respectively; P<0.05). In particular, men were 7 times, 9 times, and 5 times more likely than females to have urinary concentrations of ACE, IMI, and the sum of Neo insecticides over the 90th percentile, respectively. Even after excluding specific regions to examine the gender related patterns of neo insecticide concentration (since there was a higher number of men vs. women in the survey), males still had a higher urinary concentration of ACE, IMI, and total Neo insecticides compared to females. When comparing these findings with other studies examining urinary Neo insecticide concentration in Sri Lanka and Spain, China had a higher level of exposure to CLO and IMI. More research will be needed to assess the gender-related differences found in urinary concentration of Neo insecticides and the associated risks.
Source: Zhang, Tao, Shiming Song, Xueyuan Bai, Yuan He, Bo Zhang, Mingwei Gui, Kurunthachalam Kannan, Shaoyou Lu, Yanying Huang, and Hongwen Sun. “A nationwide survey of urinary concentrations of neonicotinoid insecticides in China.” Environment international 132 (2019): 105114.
© 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/)
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Posted February 3, 2020.
Chrystal Moulton BA, PMP, is a 2008 graduate of the University of Illinois at Chicago. She graduated with a bachelor’s in psychology with a focus on premedical studies and is a licensed project manager. She currently resides in Indianapolis, IN.
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- Zhang T, Song S, Bai X, et al. A nationwide survey of urinary concentrations of neonicotinoid insecticides in China. Environment international. 2019;132:105114.
