Analysis of drinking water quality detection capability of centers for disease control and prevention in China, 2022

Objective To investigate the drinking water quality detection capability of centers for disease control and prevention (CDCs) in China in 2022, and to provide a reference for promoting construction of water quality detection capability in CDCs.

Methods Data on water quality detection capability of CDCs at all levels in China in 2022 were collected to analyze the detection capabilities of CDCs for all indices (106 items) and conventional indices (42 items) in the Standards for Drinking Water Quality (GB 5749-2006) at different levels and in different regions. The Kruskal-Wallis H test was performed to compare the detection capabilities of CDCs at different levels and in different regions.

Results The M (P₂₅, P₇₅) values of detection capabilities for all indices of CDCs at provincial, provincial capital, prefecture, and county/district levels were 106 (104, 106), 106 (104, 106), 94 (60, 104), and 37 (33, 42), respectively, showing a significant difference (χ²=632.56, P < 0.001). The M (P₂₅, P₇₅) values of detection capabilities for conventional indicators were 42 (42, 42), 42 (42, 42), 40 (40, 42), and 36 (32, 40), respectively, showing a significant difference (χ²=396.76, P < 0.001). The pairwise comparative analysis showed that the detection capabilities of CDCs for all indices and conventional indicators were all significantly lower at county/district levels than those at provincial, provincial capital, and prefecture levels (P < 0.001 after adjustment). There were no significant differences in the detection capabilities of CDCs for all indices and conventional indices at provincial and provincial capital levels among different regions (χ² were 3.67, 4.04, 8.69, 5.42, respectively, P >0.05). There were significant differences in the detection capabilities of CDCs for all indices and conventional indices at prefecture and county/district levels among different regions (χ² were 50.16, 36.16, 177.36, 154.56, respectively, P < 0.001). The pairwise comparison showed that the detection capabilities of East China were highest, and the detection capabilities of CDCs in Northwest China were significantly lower than those of other regions (P < 0.001 after adjustment). The detection capability was the lowest for gross alpha radioactivity and gross beta radioactivity among conventional parameters, and weakest for Giardia lamblia, Cryptosporidium, microcystin, and glyphosate among non-conventional parameters.

Conclusion After more than ten years construction, there has been an improvement in the water quality detection capability of the CDC system compared with 2008, but still with a gap between the current detection capability and the requirements. The detection capability of CDCs at county/district levels and in Northwest China is relatively weak, which should be strengthened in the future.