Why is plastic so bad for our health?

Phthalates are harmful chemicals in plastics

By BCPP Director of Science Rainbow Rubin, PhD, MPH

Phthalates are compounds widely used to soften plastics. Di(2-ethylhexyl)phthalate (DEHP) is commonly used in daily life supplies and polyvinylchloride medical devices, and thus, we are exposed to phthalates through ingestion (eating), inhalation (breathing), and medical treatments such as chemotherapy.[6]

Phthalates disrupt the endocrine and reproductive system and act as cancer agents.[3] DEHP is a phthalate that has been found to have toxic effects on the testis and kidneys, as well as fertility. DEHP is an endocrine disruptor and can disrupt the balance of steroid hormones, which is significantly associated with endocrine-related cancers, such as breast cancer, prostate cancer, testicular cancer, and thyroid cancer.[5]

Scientific results suggest DEHP exposure increases the risk of cancer. One study with over 6,000 people found that elevated DEHP levels in urine were significantly associated with an increased risk of cancer, even after accounting for other risk factors such as sociodemographic factors, BMI, hypertension status, diabetes status, coronary heart disease status, drinking situation, and smoking condition.[5]

Not only does DEHP increase the risk of cancer, it makes it harder to cure cancer. Camptothecin (CPT) is an anti-cancer drug used in chemotherapy that works by stopping the tumor cells from growing and causing cell death in cancer cells. The actions of chemotherapy drugs such as CPT are impacted by plasticizers like DEHP. Scientific evidence indicates that the phthalate DEHP interferes with the effects of CPT during chemotherapy by blocking CPT’s ability to cause cell death in lung cancer cells.[1] Other studies found that serum DEHP concentrations were positively correlated with cancer recurrence in the case of both colon and breast cancers.[2,4] These findings show that DEHP could affect anticancer treatment and include evidence that DEHP induces resistance to chemotherapy.