Assessing the trend of diabetes mellitus by analyzing metformin as a biomarker in wastewater.

According to International Diabetes Federation estimates, China has the highest rate of diabetes in the world. To monitor the prevalence of diabetes mellitus (DM) in near real-time, a first-line medication for the treatment of type 2 diabetes, metformin, was used. Wastewater-based epidemiology (WBE) was applied to estimate the consumption of metformin in Dalian from 2015 to 2018. Quantification of metformin was undertaken using solid-phase extraction (SPE) and N-methyl-bis (trifluoroacetamide) derivatization prior to GC-MS analysis. The concentrations of metformin in eleven wastewater treatment plants (WWTPs) ranged from 1.7 µg/L to 239.0 µg/L, with an average value of 68.3 µg/L. For metformin consumption, there was a gradual increase from 12.1 mg/d/capita in 2015 to 28.4 mg/d/capita in 2018. Meanwhile, the prevalence of metformin in the Dalian population ranged from 1.6% in 2015 to 3.8% in 2018. Similarly, the prevalence of DM showed an increasing trend from 12.2% in 2015 to 21.6% in 2018, which is consistent with the data predicted by traditional surveys (15.2-19.8%). Additionally, the prevalence of DM in 2015 estimated based on WBE was 12.2%, which agreed with the results from the traditional survey (12.3%). These results indicated that the proposed method provided a feasible way to reveal the prevalence of DM through metformin monitoring by the WBE approach.

Wastewater analysis reveals spatial pattern in consumption of anti-diabetes drug metformin in China.

Metformin has been widely used as an oral drug for the treatment of diabetes mellitus. However, its consumption can be influenced by many economic and social factors. In this study, we investigated the spatial consumption pattern of metformin in China through wastewater-based epidemiology (WBE) approach. Influent wastewater samples were collected from 21 wastewater treatment plants (WWTPs) in 19 cities of the northeast China. A method using solid-phase extraction combined with N-Methyl-bis (trifluoroacetamide) derivatization for GC-MS detection was applied for metformin analysis. In 21 days, metformin showed high stability in wastewater at 24 °C and -20 °C. The mean concentrations of metformin in all WWTPs ranged from 2.42 µg L-1 to 53.6 µg L-1. The consumption of metformin was 0.66-15.6 mg d-1 capita-1 with the mean value of 5.54 ±â€¯4.28 mg d-1 capita-1. The prevalence of metformin ranged from 0.09% to 2.10% with an average of 0.74%. Both the consumption and prevalence of metformin displays significant spatial variations in northeast China. A statistical correlation analysis indicated that the consumption of metformin increases with the decrease of per capita disposable income of urban residents. To further predict the use of metformin in China, we developed a regress model and depicted a consumption map. The annual consumption of urban residents in Chinese provinces range from 1085-63,828 kg yr-1 with mean value of 25,347 kg yr-1, which would provide a certain reference value for public health care and diabetes control.

Reduction in methamphetamine consumption trends from 2015 to 2018 detected by wastewater-based epidemiology in Dalian, China.

BACKGROUND: Wastewater-based epidemiology (WBE) has become a useful tool in long-term or short-term continuous monitoring of illicit drugs consumption over the world. METHODS: We investigated the trend of methamphetamine (METH) use between 2015 and 2018 through WBE in Dalian, a typical Chinese city. Samples were collected in 11 municipal wastewater treatment plants (WWTPs). An analytical method, solid-phase extraction combined with trifluoroacetic anhydride derivatization prior to gas chromatography-mass spectrometry (GC-MS) analysis was applied to detect METH concentrations. RESULTS: During the sampling period, the METH concentrations increased slowly from 315 ± 243 ng/L in 2015 to 523 ± 549 ng/L in 2016, followed by a significant decrease with the concentrations 188 ± 187 ng/L in 2017 and 54.6 ± 42.9 ng/L in 2018. Ammonium nitrogen (NH4-N) was applied to estimate population size. The average coefficient of variation for population in 11 WWTPs was 35.3 ± 8.9%, reflecting the dynamic variations of population effectively. For METH consumption, there was a gradual increase from 2015 (231 mg/day/1000 people) to 2016 (414 mg/day/1000 people) and a significant linear decrease to 2017 (206 mg/day/1000 people) and 2018 (53.9 mg/day/1000 people). The prevalence of METH increased from 2015 (0.78%) to 2016 (1.06%), then decreased to 2017 (0.55%) and 2018 (0.17%), showed similar trends with the consumption. CONCLUSIONS: The obvious reduction trends of METH consumption via WBE over the period in Dalian provides objective evidence for declined METH consumption in local population. The reduction is probably due to the severe crack-down of illicit drugs by the government.

Applying a population model based on hydrochemical parameters in wastewater-based epidemiology.

Wastewater-based epidemiology combining with a population model based on hydrochemical parameters was applied in 10 wastewater treatment plants (WWTPs) in Jilin province, China. Population of WWTPs served was calculated by the model including three hydrochemical parameters ammonia nitrogen, chemical oxygen demand, and total phosphorus. The population model was constructed by using analytic hierarchy process to calculate weight factors of each hydrochemical parameters equivalent population. The size of population estimated by the model showed the highest correlations with cotinine mass load (r2=0.91, p<0.001), demonstrating better population estimation. Meanwhile daily excretion of cotinine per capita was first estimated about 0.68mg in China through liner regression analysis. In accessing the viability of the population model, the abuse of methamphetamine (METH) was calculated. Prevalence of METH use in Jilin province was calculated with an average of 0.72% based on the population model, which was similar with the result reported by United Nations World Drug Report in 2018. In assessing uncertainty of different population estimations, population model showed lower uncertainty than single hydrochemical equivalent population. These results indicate the population model based on hydrochemical parameters reduces uncertainty in population estimation and is a useful tool in monitoring illicit drug abuse.