Study of Metabolism of Deet-containing Insect Repellent in Human Volunteers

• Main Authors: Jia-Ni Tian, 田佳妮
• Other Authors: none
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/55312432772488280565

碩士 === 慈濟大學 === 公共衛生研究所 === 95 === Objective: Deet was often used as insect repellent ingredient. The metabolism of containing Deet insect repellent in adults had been studied in the past, but little is known for that in children. There raises another concern that concurrent use of Deet containing insect repellent and sunscreen may enhance the dermal absorption of Deet synergistically; however, the report lacks direct evidence of the human body test. This study is to evaluate the metabolisms of Deet in children’s and adults’ bodies, to confirm the synergistic effect by testing on human subjects, and to determine the best way to use both products simultaneously. Method: We used commercially available insect repellent and sunscreen on human subjects in the study. There were four testing scenarios: 1) applying insect repellent only;2) applying sunscreen only; 3) applying sunscreen first and insect repellent after 15 minutes; 4) applying insect repellent first and sunscreen after 15 minutes; 5) applying sunscreen and immediately insect repellent. The 20 child subjects only participated in the first scenario (8 hours for child subjects), and 9 adult subjects had to complete five scenarios. Urine samples were collected from each subject within the first 12 hours after testing, and analyzed using high performance liquid chromatography for Deet and its metabolites. Result: The mean concentration of Deet metabolites in children urine was higher than that in adult significantly (p < 0.05). The results showed that Scenario 4 had the highest Deet equivalent (mean =472.9±485.1 μg), which were significantly different from those derived from the other scenarios (p < 0.05). This indicates that the method applying insect repellent first and then sunscreen reflects the synergistic effect. The possible reason is that applying this way may mix both products more thoroughly than the other ways. Among the other experimental scenarios, there was no observed significant difference, suggesting that applying insect repellent outmost not result in excess absorption of Deet. Conclusions: The mean concentration of Deet metabolites in children urine was higher than that in adult significantly. Concurrent and mixing use of insect repellent and sunscreen resulted in high concentrations of Deet and its metabolites in urine, that is, the synergistic effect of dermal absorption of Deet. Applying sunscreen followed by insect repellent without mixing should be a better way to use the two products simultaneously.