Life in Plastic, It's [Not So] Fantastic
While microplastics have long been a concern for biohackers and health experts, they have recently gone from the bloodstream to the mainstream.
Articles about microplastics in Consumer Reports and NPR both went viral this past week. What should you make of this? What do we know about our exposure risks to these microplastics and the impact on our health?
Why is everyone talking about microplastics?
Consumer Reports tested popular foods for phthalates - a plastic additive that has been found in strikingly high quantities in many packaged and fast foods, including those purporting to be healthy. A couple of surprises were on the list. Notably the protein shakes made by Fairlife Organic, popular among Shaper editors and readers, had 20mg of phthalates per serving, Annie’s organic cheesy ravioli came in highest with 54mg per serving, and Chipotle chicken burritos had 21mg per serving.
Another article that hit the mainstream, this time by NPR, brought attention to a study showing microplastics present in 100% of the adult male cohort’s testes. The study (with 23 human participants) built on an earlier study (with only 6 participants) to show that more widespread testing should be pursued.
There’s been a ton of research on this over the past few years, showing significant potential health risks associated with regular exposure. Research consistently shows that phthalates disrupt endocrine functions, impacting reproductive health, hormonal balance, and development. Elevated phthalate levels have been linked to reduced fertility, decreased male hormone synthesis, and adverse effects on fetal and child development - including increased risks of preterm birth and cardio-metabolic issues. Phthalate exposure has also been associated with deleterious effects in organ systems ranging from the heart to the liver. The overall body of evidence supports the conclusion that phthalates pose health risks, but ongoing research continues to refine our understanding of these risks. One interesting focus here is on how widespread these chemicals are. They are found in food, human subjects, institutional buildings, and even nail salons. We’ve dug in and found the best and latest research on the subject.
The Research
Below we summarize some of the critically important and representative papers on microplastics over the last few years, with a particular focus on phthalates. Among human study cohorts they have been shown to have a serious impact on reproductive health and infertility, metabolic and oxidative stress, cancer risk, cardiovascular health, the immune system (including children’s asthma), and neurodevelopment. Exposure risks extend from more controllable areas such as consumption of packaged food to less controllable areas such as environmental and household dust. Moreover, the impacts seems to be more pronounced in children. While most research on these effects in human subjects are more recent, people have noticed the link between plasticizers and hormones/fertility in male rats since the late 1980s. Thirty-five years of results make it less likely that human results shown are a result of p-hacking or similar statistical legerdemain. With half of the world’s plastics produced in the last 15 years we are just beginning to feel the impact on chronic disease and lifespan.
Associations of environmental phthalate exposure with male steroid hormone synthesis and metabolism: An integrated epidemiology and toxicology study.
Journal: Journal Of Hazardous Materials
Authors: Meiping Tian, Shuangshan Wu, Yi-Xin Wang, Liangpo Liu, Jie Zhang, Heqing Shen, Yanyang Lu, Huaqiong Bao, Qingyu Huang
Publication Date: 2022-08-15
SHAPER's Take: This study investigates the negative impact of phthalate exposure on male hormonal balance, which affects reproductive health and overall wellbeing. Hormone synthesis is one of the largest concerns for people worried about these chemicals, and this is one of the more thorough papers we could find on the topic.
Abstract: Humans are simultaneously and constantly exposed to various lipophilic chain phthalate acid esters. The association of urinary phthalate metabolites with altered male steroid hormone synthesis and metabolism was examined using epidemiology and toxicology studies. We measured 8 phthalate metabolites [monomethyl phthalate (MMP), monoethyl phthalate (MEP), mono-n-butyl phthalate (MBP), mono-benzyl phthalate (MBzP), mono-n-octylphthalate (MOP), mono-(2-ethylhexyl) phthalate (MEHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono (2-ethyl-5-oxohexyl) phthalate (MEOHP)] and two sex hormones [testosterone (T) and estradiol (E2)] in single serum and repeated spot urine samples among 451 reproductive-age males. Moreover, in vitro experiments with Leydig cell MLTC-1 steroidogenesis and liver cell HepG2 efflux in response to mixed and individual phthalates were designed to simulate real-world scenarios of human exposure. As a joint mixture, the phthalate metabolite was inversely associated with serum T and E2 concentrations but positively associated with urinary T and E2 concentrations. Combined with in vitro experiments, DEHP metabolites were identified as the predominant contributor to the decline in hormone synthesis, and ATP-binding cassette (ABC) gene activation might be involved in hormone excretion. Exposure to environmentally relevant phthalates was associated with both altered steroid synthesis and excretion, which provides additional insights into the endocrine-disrupting potential of phthalates.
Paternal exposures to environmental chemicals and time-to-pregnancy: overview of results from the LIFE study.
Journal: Andrology
Authors: G M Buck Louis, D B Barr, K Kannan, Z Chen, S Kim, R Sundaram
Publication Date: 2016-07-04
SHAPER's Take: The online discourse on microplastics has focused on the “xenoestrogen” effect in men. This is one of the studies that shows this, concentrating on potential reduced fertility in men, emphasizing the often underestimated role of paternal health in reproductive success. By identifying specific chemicals that reduce fecundity, including phthalates, this research offers insight for people concerned about these effects as well as public health initiatives aimed at improving reproductive health outcomes (potentially including regulations on harmful environmental exposures)
Abstract: Published findings from the Longitudinal Investigation of Fertility and the Environment (LIFE) Study regarding the relation between environmental chemicals and couple fecundity, as measured by time-to-pregnancy (TTP), are reviewed with a particular focus on role of the male partner. The LIFE Study recruited 501 couples from 16 counties in two U.S. states upon discontinuing contraception for purposes of becoming pregnant. Upon enrollment, couples provided a blood and urine sample for the quantification of persistent and non-persistent environmental chemicals, respectively, and then completed daily journals until pregnant or up to one year of trying. Female partners used fertility monitors to aid the timing of intercourse relative to ovulation, and digital home pregnancy test kits on the day of expected menses. Chemical classes included: metals, persistent organic pollutants, environmental phenols, and phthalates that were quantified using inductively coupled plasma mass spectrometry or isotope dilution high-resolution or tandem mass spectrometry. Time-to-pregnancy (TTP) was defined as the number of prospectively observed menstrual cycles required for pregnancy. Fecundability odds ratios (FORs) and 95% confidence intervals (CIs) were estimated for each chemical and partner after adjusting for potential confounders and accounting for right censoring and time off contraception. FORs < 1 are suggestive of diminished fecundity or a longer TTP. Significant reductions (ranging from 17-31%) in couple fecundity were observed for male partners' concentration of lead (0.83; 0.70, 0.98), 2,2',4,4'-tetrahydroxybenzophenone (0.69; 0.49, 0.97), monobenzyl (0.80; 0.67, 0.97), and monomethyl (0.81; 0.70, 0.94) phthalates after adjusting for the female partners' concentrations. Seven PCB congeners quantified in men's serum were associated with a 17-29% reduction in couple fecundity. Our findings underscore the importance of a couple-based exposure design, inclusive of the male partner, when assessing couple-dependent outcomes such as TTP to avoid misinterpretation of results based only upon the female partner.
Update about the disrupting-effects of phthalates on the human reproductive system.
Journal: Molecular Reproduction And Development
Authors: Inês Mesquita, Margarida Lorigo, Elisa Cairrao
Publication Date: 2021-10-06
SHAPER's Take: This is a great review of papers related to phthalates impact on reproductive health for both men and women, including infertility risks in men - a good starting point for people that want to get caught up on how phthalates disrupt the endocrine and reproductive system.
Abstract: Phthalate esters are synthetic chemicals used in the plastic industry as plasticizers and consumable products. According to United Nations, about 400 million tons of plastic are produced every year. In parallel with increased production, the concerns about its effects on human health have increased because phthalates are endocrine-disrupting compounds. Humans are continuously exposed to phthalates through different routes of exposure. Experimental data have associated phthalate exposure to adverse effects on development and reproduction in women (e.g., earlier puberty, primary ovarian insufficiency, endometriosis, preterm birth, or in vitro fertilization) and men (e.g., anogenital distance, cryptorchidism, hypospadias, and changes in adult reproductive function) although there is no consensus. Therefore, one question arises: could the increase in infertility be related to phthalate exposure? To answer this question, we aimed to assess the disrupting-effects of phthalates on the human reproductive system. For this, we reviewed the current literature based on epidemiological and experimental data and experimental studies in humans. The phthalate effects were discussed in a separate mode for female and male reproductive systems. In summary, phthalates induce toxicity in the reproductive system and human development. The increased plastic production may be related to the increase in human infertility.
Effects of phthalates on normal human breast cells co-cultured with different fibroblasts.
Journal: Plos One
Authors: Fang-Ping Chen, Mei-Hua Chien, Huang-Yang Chen, Yuet-Tong Ng
Publication Date: 2018-06-25
SHAPER's Take: Many people focus on the hormonal effects of phthalates on male infertility and testosterone levels, but they likewise seem to have an outsized effect on cancer risk for women. The study shows the potential endocrine-disruptive effects of phthalates on breast cell proliferation, particularly their capacity to behave similarly to estrogen. This paper suggests that even at low concentrations, phthalates could contribute to breast cancer development by influencing hormonal activities and cellular interactions in mammary tissues.
Abstract: Whether or not phthalates play a role in breast carcinogenesis remains to be determined. The goal of this study was to explore the effects of phthalates on the growth of normal MCF-10A breast cells modulated by breast fibroblasts. Fibroblasts were derived from normal mammary tissue adjacent to both estrogen receptor (ER) positive and negative primary breast cancers, which were grown separately from nontumorigenic MCF-10A epithelial cells. MCF-10A co-culture cells were treated with 10 nM 17β-estradiol (E2), Butyl benzyl phthalate (BBP), di(n-butyl) phthalate (DBP), and di(20ethylhexyl) phthalate (DEHP) (10 and 100 nM). After incubation for 120 hours, the cells were harvested and extracted for MTT assay. Western blot analysis was used to evaluate the proliferative pathway proteins and the effects on ER α. Only fibroblasts from ER (+) breast cancer significantly stimulated proliferation of MCF-10A cells. Exposure of the co-culture to E2, BBP, DBP, DEHP, and E2 combined with one of these phthalates resulted in significantly increased cell proliferation, as well as proliferating cell nuclear antigen (PCNA) and ER α expressions. The present study demonstrates that phthalates express a significant influence in fibroblast-epithelial interactions, similarly to the effects of E2 on breast cells. The effects of phthalates on normal breast cells depend upon ER modulating actions. In breast carcinogenesis, phthalates should be considered as having endocrine disrupting potential, even at low concentrations.
Phthalate Exposure and Coronary Heart Disease: Possible Implications of Oxidative Stress and Altered miRNA Expression.
Journal: Chemical Research In Toxicology
Authors: Asmaa Mohammad Moawad, Sara Awady, Abla Abd El Rahman Ali, Marwa Abdelgwad, Soliman Belal, Sarah Hamed N Taha, Marwa Issak Mohamed, Fatma Mohamed Hassan
Publication Date: 2024-05-20
SHAPER's Take: Moawad et al.'s research highlights the link between phthalate exposure and increased risk of coronary heart disease, suggesting oxidative stress and changes in miRNA expression as underlying mechanisms. This finding is crucial as it points to the potential for specific biomarkers for early detection and possibly an opportunity for targeted interventions to mitigate this risk.
Abstract: The relationship between phthalate exposure and coronary heart disease (CHD) is still unclear. This study aimed to investigate the association between phthalate exposure and CHD and determine the possible atherogenic mechanisms of phthalates by assessing oxidative stress and altering miRNA expression. This case-control study included 110 participants (55 CHD patients and 55 healthy controls). The levels of oxidative stress markers, malondialdehyde (MDA), and superoxide dismutase (SOD), and the expression of miRNA-155 (miR-155) and miRNA-208a (miR-208a), were measured and correlated with the urinary mono-2-ethylhexyl phthalate (MEHP). Highly significant differences were detected between the CHD cases and the control group regarding MEHP, MDA, SOD, miR-155, and miR-208a (p-value < 0.001). Spearman correlations revealed a significant positive correlation between MDA and MEHP in urine (P = 0.001 and rs = 0.316) and a significant negative correlation between SOD and MEHP in urine (P < 0.001 and rs = -0.345). Furthermore, significant positive correlations were observed between miR-155 and urinary MEHP (P = 0.001 and rs = 0.318) and miR-208a and urinary MEHP (P < 0.001 and rs = -0.352). This study revealed an association between phthalate exposure, as indicated by urinary MEHP and CHD; altered expression of miR-155 and miR-208a and oxidative stress could be the fundamental mechanisms.
Relationship between phthalates exposures and metabolic dysfunction-associated fatty liver disease in United States adults.
Journal: Plos One
Authors: Junhao Sun, Siqi Yang, Yue Zhang, Wenzhi Xiang, Xiubo Jiang
Publication Date: 2024-04-22
SHAPER's Take: Sun et al. reveal potential health risks linked to phthalates, common chemicals found in many everyday products, by demonstrating their association with increased risk of fatty liver disease tied to metabolic dysfunction in adults. This connection is especially concerning given the widespread use of phthalates and the rising prevalence of metabolic disorders. Their findings prompt reconsideration of phthalate exposure in everyday consumer products, emphasizing the need for further research and potential regulatory review.
Abstract: As a new definition for the evidence of hepatic steatosis and metabolic dysfunctions, the relationship between phthalates (PAEs) and metabolic dysfunction-associated fatty liver disease (MAFLD) remains virtually unexplored. This study included 3,137 adults from the National Health and Nutrition Examination Survey spanning 2007-2018. The diagnosis of MAFLD depended on the US Fatty Liver Index (US FLI) and evidence of metabolic dysregulation. Eleven metabolites of PAEs were included in the study. Poisson regression, restricted cubic spline (RCS), and weighted quantile sum (WQS) regression were used to assess the associations between phthalate metabolites and MAFLD. After adjusting for potential confounders, Poisson regression analysis showed that mono-2-ethyl-5-carboxypentyl phthalate (MECPP), mono-n-butyl phthalate, mono-(3-carboxypropyl) phthalate, mono-ethyl phthalate (MEP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate were generally significant positively associated with MAFLD (P<0.05). Furthermore, the WQS index constructed for the eleven phthalates was significantly related to MAFLD (OR:1.43; 95%CI: 1.20, 1.70), MEHHP (33.30%), MEP (20.84%), MECPP (15.43%), and mono-isobutyl phthalate (11.78%) contributing the most. This study suggests that exposure to phthalates, individually or in combination, may be associated with an increased risk of MAFLD.
Combined effects of prenatal phthalate exposure on cardiometabolic risk score among 4- to 7-year-old children: MABC study.
Journal: Chemosphere
Authors: Hui Gao, Meng-Long Geng, Juan Tong, Bao-Lin Wang, Kun Huang, Yi Zhang, Hong Gan, Bei-Bei Zhu, Peng Ding, Qu-Nan Wang, Jian-Qing Wang, Cheng Zhang, Peng Zhu, Fang-Biao Tao
Publication Date: 2023-01-01
SHAPER's Take: It’s shocking to see the variety of different negative health effects that have been reproducibly linked to phthalates across women, men, and children. This study digs into the effects on children and how different timings and types of prenatal phthalate exposure can distinctly influence cardiometabolic health in early childhood. Understanding these associations helps in developing targeted interventions to improve cardiometabolic health outcomes from a young age, thereby reducing the risk of related diseases later in life.
Abstract: There is currently no consensus about the impact of prenatal phthalate exposure on blood pressure and glycolipids in children. Few studies consider the health effects as an integrated indicator. The combined effect of multiple phthalate exposures is often ignored. Based on the Ma'anshan Birth Cohort, 2298 woman-child pairs were included in this study. Maternal urine was collected in each trimester to analyze 6 phthalate metabolites. The overall cardiometabolic risk (CMR) score was calculated based on serum glycolipids and blood pressure for children aged 4-7 years. A higher score represents a less favorable CMR profile. The restricted cubic spline model was used to explore the relationship between prenatal phthalate exposure and childhood CMR score. In addition, the quantile g-computation and the Bayesian kernel machine regression were used to evaluate the combined effect. The MBP exposure in the 1st trimester (MBP-1st) and the MEP-2nd were non-linearly associated with the CMR score (Fnonlinear = 3.28 and 5.60, Pnonlinear = 0.0378 and 0.0038, respectively). The MBP-3rd (Flinear = 5.31, Plinear = 0.0012) and the ∑LMWP-3rd (Flinear = 4.37, Plinear = 0.0045) were negatively associated with the score in a linear manner. The phthalate mixture in the 2nd trimester increased the score (psil = 0.1747, 95% CI = 0.0077-0.3416), with the MEP being the most common [weights = 0.5290; posterior inclusion probability (PIP) = 0.40]. The phthalate mixture in the 3rd trimester decreased the score (psil = -0.2024, 95% CI = -0.4097－0.0048), with the MEHP (weights = -0.5101; PIP = 0.14) and the MBP (weights = -0.3993, PIP = 1.00) being the greatest contributors. In conclusion, the MBP-1st and the MEP-2nd are non-linearly associated with the cardiometabolic risk in children. The MBP-3rd and the ∑LMWP-3rd decrease the childhood risk. The combined exposure to phthalate mixture in the second and third trimester elevates and decreases the risk of childhood cardiometabolism, respectively.
Modulation of fetoplacental growth, development and reproductive function by endocrine disrupters.
Journal: Frontiers In Endocrinology
Authors: Sanjay Basak, Saikanth Varma, Asim K Duttaroy
Publication Date: 2023-10-03
SHAPER's Take: Basak et al.'s research underscores the potential health risks associated with prenatal exposure to common chemicals like bisphenols and phthalates. It highlights how these substances can alter fetoplacental development and have long-term effects on the metabolic and reproductive functions of the offspring. The study is particularly compelling as it connects everyday chemical exposure to critical changes in hormonal and developmental processes during pregnancy.
Abstract: Maternal endocrine homeostasis is vital to a successful pregnancy, regulated by several hormones such as human chorionic gonadotropin, estrogen, leptin, glucocorticoid, insulin, prostaglandin, and others. Endocrine stress during pregnancy can modulate nutrient availability from mother to fetus, alter fetoplacental growth and reproductive functions. Endocrine disrupters such as bisphenols (BPs) and phthalates are exposed in our daily life's highest volume. Therefore, they are extensively scrutinized for their effects on metabolism, steroidogenesis, insulin signaling, and inflammation involving obesity, diabetes, and the reproductive system. BPs have their structural similarity to 17-β estradiol and their ability to bind as an agonist or antagonist to estrogen receptors to elicit an adverse response to the function of the endocrine and reproductive system. While adults can negate the adverse effects of these endocrine-disrupting chemicals (EDCs), fetuses do not equip themselves with enzymatic machinery to catabolize their conjugates. Therefore, EDC exposure makes the fetoplacental developmental window vulnerable to programming in utero. On the one hand prenatal BPs and phthalates exposure can impair the structure and function of the ovary and uterus, resulting in placental vascular defects, inappropriate placental expression of angiogenic growth factors due to altered hypothalamic response, expression of nutrient transporters, and epigenetic changes associated with maternal endocrine stress. On the other, their exposure during pregnancy can affect the offspring's metabolic, endocrine and reproductive functions by altering fetoplacental programming. This review highlights the latest development in maternal metabolic and endocrine modulations from exposure to estrogenic mimic chemicals on subcellular and transgenerational changes in placental development and its effects on fetal growth, size, and metabolic & reproductive functions.
Prenatal exposure to phthalates and neurocognitive development in children at two years of age.
Journal: Environment International
Authors: Xi Qian, Jiufeng Li, Shunqing Xu, Yanjian Wan, Yuanyuan Li, Yangqian Jiang, Hongzhi Zhao, Yanqiu Zhou, Jiaqiang Liao, Hongxiu Liu, Xiaojie Sun, Wenyu Liu, Yang Peng, Chen Hu, Bin Zhang, Shi Lu, Zongwei Cai, Wei Xia
Publication Date: 2019-10-01
SHAPER's Take: Qian et al.'s research highlights the potential negative impacts of prenatal exposure to phthalates on children's psychomotor development, particularly regarding lower molecular weight phthalates. This shows a particular risk related to dietary consumption of phthalates during pregnancy, as they enter the fetal bloodstream.
Abstract: Phthalates are a family of endocrine disruptors with short elimination half-lives in the human body. To date, few epidemiological studies have examined repeated measures of maternal urinary phthalates and the combined effects of prenatal exposure to multiple phthalates on children's neurocognitive development. We aimed to investigate the association between children's neurocognitive development at 2 years of age and prenatal phthalate exposure, as assessed by repeated measurements during pregnancy, and to further examine the effects of co-exposure to multiple phthalates using cumulative risk assessment. Within a prenatal cohort in Wuhan, China, we measured five high-molecular-weight (HMW) phthalates and three low-molecular-weight (LMW) phthalate metabolites' concentrations in three urine samples collected in the 1st, 2nd, and 3rd trimester of pregnancy from each mother. We assessed neurocognitive development by Bayley Scales of Infant and Toddler Development (BSID) at 2 years of age (n = 476) to obtain the children's mental development index (MDI) and psychomotor development index (PDI). Higher exposure levels to LMW phthalates compared to HMW phthalates were observed in our population. Ln-transformed averaged concentration of mono-n-butyl phthalate (MnBP), a metabolite of the LMW phthalate di-n-butyl phthalate (DnBP) during pregnancy, was associated with decreased PDI scores in all children (β = -1.90, 95% CI: -3.43, -0.37). Similarly, the averaged sum concentration of ∑dibutyl phthalate (∑DBP) was associated with decreased PDI scores in all children (β = -1.89, 95% CI: -3.63, -0.15). A negative trend of association between exposure to HMW phthalates and PDI scores was observed in girls, while a positive association was found in boys. In cumulative risk assessment analyses, we consistently observed that the hazard quotient of DnBP (the parent compound of MnBP) was inversely associated with PDI scores in all children, whereas the hazard quotient of di-2-ethylhexyl phthalate (DEHP), an HMW phthalate, was positively associated with PDI scores in boys only. This study is the first to use repeated measurement of maternal urinary phthalates in all three trimesters to assess prenatal exposure in relation to children's neurodevelopment. Our study suggested a negative association between prenatal exposure to MnBP and children's psychomotor development, and potentially sex-specific associations between HMW phthalates and neurocognitive development among boys and girls. These findings warrant further confirmation.
Human Erythrocytes Exposed to Phthalates and Their Metabolites Alter Antioxidant Enzyme Activity and Hemoglobin Oxidation.
Journal: International Journal Of Molecular Sciences
Authors: Paulina Sicińska, Kinga Kik, Bożena Bukowska
Publication Date: 2020-06-24
SHAPER's Take: Sicińska et al.'s research reveals the potential health risks associated with phthalate exposure by demonstrating how these chemicals disrupt the redox balance in human erythrocytes (red blood cells). This imbalance, evidenced by altered antioxidant enzyme activity and increased hemoglobin oxidation, leads to the premature removal of these red blood cells from circulation, potentially leading to anemia, hypoxia, and cardiovascular disease.
Abstract: Phthalates used as plasticizers have become a part of human life because of their important role in various industries. Human exposure to these compounds is unavoidable, and therefore their mechanisms of toxicity should be investigated. Due to their structure and function, human erythrocytes are increasingly used as a cell model for testing the in vitro toxicity of various xenobiotics. Therefore, the purpose of our study was to assess the effect of selected phthalates on methemoglobin (metHb), reactive oxygen species (ROS) including hydroxyl radical levels, as well as the activity of antioxidative enzymes, such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), in human erythrocytes. Erythrocytes were incubated with di-n-butyl phthalate (DBP), butylbenzyl phthalate (BBP), and their metabolites, i.e., mono-n-butyl phthalate (MBP) and monobenzyl phthalate (MBzP), at concentrations ranging from 0.5 to 100 µg/mL for 6 or 24 h. This study shows that the analyzed phthalates disturbed the redox balance in human erythrocytes. DBP and BBP, at much lower concentrations than their metabolites, caused a statistically significant increase of metHb and ROS, including hydroxyl radical levels, and changed the activity of antioxidant enzymes. The studied phthalates disturbed the redox balance in human erythrocytes, which may contribute to the accelerated removal of these cells from the circulation.
Phthalates in House and Dormitory Dust: Occurrence, Human Exposure and Risk Assessment.
Journal: Bulletin Of Environmental Contamination And Toxicology
Authors: Shen Xu, Chao Li
Publication Date: 2021-02-18
SHAPER's Take: Xu et al.'s research highlights the significant presence of phthalates in indoor environments. The study reveals that especially vulnerable groups such as infants, toddlers, children, and teenagers are at notable risk of DEHP exposure, surpassing safety thresholds. This brings attention to the need for stricter regulations and mitigation measures to protect these sensitive populations from potential health hazards associated with phthalate pollution in everyday living spaces.
Abstract: Phthalates are one of ubiquitous contaminants in the indoor environment. In this study, we analyzed concentrations and profiles of 9 phthalates in dust samples collected from houses and university dormitories in Nanjing, China. The total concentrations of phthalates in house and dormitory dust ranged from 111.4 to 3599.1 µg/g and 86.1 to 1262.3 µg/g, respectively. Phthalates in house was significantly higher than that in dormitory dust (p < 0.01). Di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP) and di-isobutyl phthalate (DiBP) were the three predominant compounds and accounted for more than 98% of total phthalates in the two microenvironments. The estimated daily intake (EDI) of phthalates, carcinogenic risk (CR) of DEHP, and hazard index (HI) values of DEHP, DBP and DiBP were estimated. Except for adults, the CR of DEHP for four subgroups (infants, toddlers, children, and teenagers) had exceeded the limitation, implying that they are at the risk of exposure to DEHP through dust ingestion.
Associations between Children's asthma and allergic symptoms and phthalates in dust in metropolitan Tianjin, China.
Journal: Chemosphere
Authors: Changqi Zhu, Yuexia Sun, Yuxuan Zhao, Jing Hou, Qingnan Zhang, Pan Wang
Publication Date: 2022-09-01
SHAPER's Take: Zhu et al. demonstrate that higher phthalate levels in household dust correlate with increased asthma and allergic symptoms in children, highlighting potential health risks from everyday exposure to these chemicals. Their findings are particularly compelling as they establish a dose-response relationship between diisobutyl phthalate concentrations and asthma, suggesting that reducing phthalate exposure in homes could mitigate some respiratory issues in children.
Abstract: Prevalences of allergies and asthma have increased through the past few decades around the world, especially in countries and regions that have adopted modern lifestyles. Epidemiological studies outside of China have found a relationship between phthalates concentrations in indoor dust and symptoms of respiratory, skin and nose allergies. The aim of our study is to investigate the association between children's asthma and allergic symptoms and concentrations of different phthalates in settled dust samples collected from children's homes in metropolitan Tianjin (Tianjin and Cangzhou), China. We selected 126 cases with current allergic symptoms and 254 controls without allergic symptoms from the cohort of 7865 children. We collected dust samples from children's bedroom and analyzed them for their content of diethyl phthalate (DEP), diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), butylbenzyl phthalate (BBzP), di-2-ethylhexyl phthalate (DEHP) and diisononyl phthalate (DiNP). We found a higher concentration of DEP in rhinitis children's homes (0.33 vs. 0.27 μg/g dust) and a higher concentration of DiBP in asthma children's homes (29.04 vs. 15.66 μg/g dust). The concentration of DiBP was significantly associated with diagnosed asthma (adjusted odds ratio (AOR): 1.30; 95% confidence interval (CI): 1.07, 1.57). A dose-response relationship was found between concentrations of DiBP in dust and asthma. This study shows that some phthalates are associated with allergic and asthma symptoms in children.
Effects of co-administration of Di(2-ethylhexyl)phthalate and testosterone on several parameters in the testis and pharmacokinetics of its mono-de-esterified metabolite
Journal: Toxicology
Author: Shinshi Oishi
Publication Date: 1989
SHAPER's Take: This is one of the first papers showing a strong effect of plasticizers on reproductive function in mammals. It’s from 1989! You’ll want to take this one with a grain of salt as studies in rats don’t consistently replicate in humans. One fun note - the paper has one author, unheard of for a medical paper today.
Abstract: The administration of 1 g/kg di(2-ethylhexyl) phthalate (DEHP) or 5 mg/kg testosterone for 1 week did not affect the testicular and prostatic gland weights in rats. However, co-administration of DEHP and testosterone induced severe testicular atrophy accompanied by a decrease of zinc concentration in the testis and reduction of the activity of testicular specific lactate dehydrogenase isozyme. These changes were similar to the results of high dose administration of DEHP alone. Values of biological half-life and area under the concentration-time curve (AUC) of mono(2-ethylhexyl)phthalate, the main metabolite of DEHP, in testes after a single co-administration of DEHP (p.o.) and testosterone (i.p.) were higher than those after DEHP administration alone. Resuits suggest that the co-administration of DEHP and testosterone enhanced the adverse effects of DEHP on testes as the result of changes in pharmacokinetic values of MEHP.