A panel study of associations between phenolic compound exposure and blood lipid levels

Abstract

BackgroundPhenolic compounds, which are widely used as plasticizers, antibacterial agents, and preservatives in industrial production, have endocrine disrupting effects on humans. Previous epidemiological studies on the associations between phenolic compound exposure and blood lipids are mainly based on single measurement of spot urine samples, neglecting potential lag effects of phenolic compounds, and the conclusions are inconsistent. ObjectiveTo investigate the effects of short-term exposure to phenolic compounds at different lag days on blood lipid levels in adults. MethodsWe recruited 143 adults (43 males and 100 females) in Wuhan for three consecutive seasonal rounds of repeated visits: summer and autumn rounds of 2017 and winter of 2018. Morning urine samples were collected for four consecutive days during each round. A set of questionnaires were also distributed on the first day. Physical examinations and fasting venous blood sample collection were conducted on the fourth day. A total of 126 adults were included for analysis (340 person-time, 1251 urine samples). The concentrations of six urinary phenolic compounds [bisphenol A (BPA), bisphenol S (BPS), triclosan (TCS), methyl paraben (MeP), ethyl paraben (EtP), and propyl paraben (PrP)] were determined by ultra-high-performance liquid chromatography-tandem mass spectrometry. Linear mixed-effect models (LMEs), multiple informant models, and generalized linear models were utilized to estimate the associations of urinary phenolic compounds at different lag days with total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), and the ratio of TG to HDL-C (TG/HDL-C). Stratified analyses were conducted by selected characteristics. ResultsAfter covariate and multiple adjustments, the LMEs indicated that a change in urinary BPA at lag 0 day from the low concentration group (<LOD) to the high concentration group (≥LOD) was associated with a 16.48% (95%CI: 4.41%, 29.94%) increase in TG/HDL-C (P FDR<0.05), and this association was more pronounced in men (P interaction=0.028) and smokers (P interaction=0.040). In addition, a change in urinary TCS at lag 2 day from the low concentration group (<LOD) to the high concentration group (≥LOD) was associated with a 13.22% (95%CI: 3.73%, 23.56%) increase in TG (P FDR<0.05). The positive association of TCS with TG was more evident in subjects aged < 50 years (P interaction=0.037). No significant associations were found between urinary phenolic compounds at other lag days and blood lipids. ConclusionShort-term exposures to BPA and TCS are positively correlated with unfavorable changes in blood lipids in adults, and the association seem to be more pronounced in men, smokers, or individuals aged < 50 years.

Keywords

• phenolic compound
• blood lipid
• linear mixed-effect models
• adult
• panel study