Study On The Biological Distribution And Male Reproductive Toxicity Of 3-Chloro-1,2-Propanediol In Rats Based On QuEChERs GC/MS

3-monochloropropane-1,2-diol（3-MCPD）is a common chloropropanol pollutant widely present in various foods such as soy sauce,vegetable oil,and infant formula.It has a variety of toxic effects,including hepatotoxicity,nephrotoxicity,immunotoxicity,neurotoxicity and carcinogenicity.Kidney and testis are its main target organs.Research has found that a certain dose of 3-MCPD treatment can cause irreversible damage to the fertility of male rats.In order to elucidate the toxicity differences of 3-MCPD in different tissues of the body,it is urgent to systematically evaluate its biological distribution in various target organs.However,there is currently a lack of detection methods for 3-MCPD content in various biological samples,such as serum,liver and kidney tissue,brain tissue,and testicular tissue.Therefore,based on Qu ECHERS-GC/MS technology,this study developed a method suitable for analyzing 3-MCPD in various biological samples by optimizing different adsorbent combinations;Using this method,the content of 3-MCPD in the blood and tissues of male rats exposed to acute and subchronic conditions was measured,and its distribution and enrichment in the rat body were evaluated;At the same time,the protective effects of different foodborne substances on reproductive dam-age caused by 3-MCPD were further explored.This study fills the gap in the detection method of 3-MCPD in biological samples,provides new data and technical support for the toxicological research of 3-MCPD,and opens up new ideas for the mitigation of re-productive toxicity of 3-MCPD.The specific research content is as follows:（1）To modified the QuECHERS pre-treatment process,we optimized the extraction solvent,extraction method,and extraction time.The results showed that the recovery rate was highest when 1.5 m L of ethyl acetate was left to stand for 30 minutes for extraction.Secondly,for serum and different tissues,the combination of adsorbents was optimized using recovery rate and matrix effect as indicators.80mg C₁₈ was selected as the serum adsorbent,40 mg PSA,40 mg C₁₈,40 mg GCB as the liver and kidney tissue adsorbent,40 mg PSA,80 mg Florisilica as the testicular adsorbent,and 80 mg C₁₈,40 mg Florisilica as the brain tissue adsorbent.Finally,a 3-MCPD analysis method suitable for blood and various tissues was developed.After method validation,the linear range of this method is2-2000 ng/m L（tissue sample 2-2000 ng/g）,LOD is 0.63 ng/m L（tissue sample 0.68-0.8ng/g）,LOQ is 2 ng/mL（tissue sample 2 ng/g）,intraday precision is 1.1-7.0%,and intraday precision is 2.2-9.5%.（2）In order to evaluate the distribution and enrichment of 3-MCPD in rats,this study established acute and subchronic exposure male rat models of 3-MCPD.The methods obtained from the above experiments were used to measure the dynamic changes of 3-MCPD content in various tissues of rats after 24 hours of gastric administration of 100mg/kg body weight,as well as the enrichment of 3-MCPD in various tissues of high（40mg/kg body weight）and low（10 mg/kg body weight）dose groups of rats after 4 weeks of exposure.The results showed that 3-MCPD could be detected in blood,liver,kidneys,testes,and brain tissues.The content of 3-MCPD in each tissue sharply increased to its peak within 30 minutes,then rapidly decreased within 2 hours,and stabilized within 12hours.24 hours after gavage,3-MCPD persisted in the kidneys（301.98 ng/m L）,testes（134.89 ng/mL）,and liver（286.98 ng/mL）;After 4 weeks of exposure,the content of 3-MCPD in various tissues of the high-dose group was significantly higher than that of the low-dose group by 34%-475.6%.In both the high-dose and low-dose groups,the enrich-ment coefficients of the kidneys were the highest（3.03%and 5.6%）,while the enrichment coefficients of the brain were the lowest（0.23%and 0.16%）.（3）In order to further study the alleviating effect of food derived substances on the reproductive toxicity of 3-MCPD,we selected procyanidins and taurine to intervene in male rats with subchronic exposure to 3-MCPD in this study.The results showed that compared with the model group,the taurine group showed no significant differences in various indicators such as 3-MCPD content in the testes,relative organ weight of the testes,and abnormal sperm rate.After the intervention of procyanidins,the 3-MCPD con-tent in the testes decreased by 53%,the relative organ weight of the testes increased by29%,and the abnormal sperm rate decreased by 22%.H&E staining results showed sig-nificant recovery in testicular tissue structure damage and sperm count in the epididymis compared to the model group.This indicated that proanthocyanidins have a potential pro-tective effect on reproductive damage caused by 3-MCPD.