Is Recycling an Integral Element of the Circular Economy?
As global attention intensifies on the plastic crisis, there is a growing emphasis on fostering a circular economy (CE) across various sectors. CE aims to shift away from the unsustainable linear model of material use and disposal towards a more sustainable, cyclic system where materials are produced, utilized, reused, and recycled, thus reducing resource extraction, energy consumption, and pollution.
In recent years, the concept of Circular Economy (CE) applied to plastic has increasingly revolved around plastic recycling, touted by the industry as a remedy for plastic pollution. While the ideal scenario entails recycled materials being repurposed into new products, thereby reducing the reliance on virgin plastic, the reality often leads to downcycling. Unlike true recycling, downcycling results in materials of inferior quality, diminishing the value of the product with each recycling cycle. Research indicates that only a small fraction of plastic waste undergoes efficient recycling, with a significant portion either being downcycled or lost during the process, underscoring the hurdles in achieving genuine circularity within the plastic recycling framework.
Impact of Chemicals Found in Recycled Plastic on Human Health
The following is a summary of some of the most significant epidemiological studies conducted in order to understand the impact of these chemicals on human health.
i. Reproductive health: Exposure to chemicals found in plastics has been associated with adverse reproductive effects, as indicated by numerous studies. Phthalates, including DEHP, DEP, DMP, and DnBP, have been linked to early onset of menstruation and accelerated breast development in young girls, along with an increased risk of breast cancer and endometriosis. Additionally, phthalates exhibit anti-androgenic properties, disrupting the activity of male hormones such as testosterone.
BPA and NP have been observed to decrease the anogenital distance in males, contributing to a decline in male fertility. Specifically, BPA is known to interfere with the function of both male and female sex hormones. Lead (Pb) has the potential to disrupt sex hormones and destabilize chromatin, potentially resulting in congenital disabilities.
Cadmium (Cd) can diminish sperm motility in males, disrupt ovarian morphology, and decrease egg count, ultimately affecting female fertility. Moreover, chlorinated paraffins (CPs) have been shown to impair the reproductive system, causing premature breast development in females and leading to reduced semen quality in men.
ii. Pregnancy and foetal development: BPA has also been known to impact child brain development, prompting regulatory controls on its usage in baby bottles and other containers for food and drinks intended for children. Pb can pass through the placenta and cause miscarriages, or low birth weight of foetuses Cd may disturb the growth and development of follicles, leading to spontaneous abortion and birth defects in infants. CPs can cause preterm birth in humans. Parental exposure to DEHP, DBP and DiBP is also associated with child verbal comprehension, processing speed, perceptual reasoning, working memory, neuropsychological disorders and mental retardation.
iii. Respiratory illness: Phthalates are known to trigger respiratory illness such as asthma, causing impairment and deterioration of the lungs.
iv. Dermal and skin issues: Heavy metals present in plastics can pose a toxicity risk that manifests in skin-related problems. Accumulation of heavy metals within the body can result in skin pigmentation abnormalities and increase the risk of developing skin cancer. Exposure to chlorinated paraffins (CPs) can also lead to skin irritation and various related dermatological issues.
v. Endocrine Disruption: In young children, exposure to phthalates has been associated with effects on metabolic activity, as well as disruptions in the endocrine and reproductive systems. Similarly, BPA and NP are recognized as endocrine-disrupting chemicals. These substances have the ability to mimic estrogen and bind to endocrine receptors, thereby causing disruption to the endocrine system.
vi. Carcinogenicity: Phthalates, CPs, BP and NP and heavy metals (Pb, Cd, As and Cr) found in plastic are mutagenic and carcinogenic.
vii. Cardiovascular system: Phthalates are recognized for their association with cardiovascular risks, including fluctuations in blood pressure, coronary heart diseases, and atherosclerosis. A particular study conducted within the Uppsala community, focusing on individuals aged 70 years or older, unveiled a significant correlation between phthalates and BPA in the development of coronary heart disease.
viii. Erythrocytes (Red blood cells): Phthalates, such as DEHP, impact the plasma membrane of erythrocytes, resulting in increased osmotic fragility by enhancing their flexibility. This ultimately distorts the shape of the erythrocytes, thereby impairing the integrity of the entire cell.
ix. Apoptosis (programmed cell death) and DNA damage: NP may induce apoptosis and chromosomal damage, eventually affecting the DNA. BPA also causes DNA damage in human blood cells.
Apart from these health effects, these chemicals can also cause liver impairment and immunotoxicity, neurological and renal damage, tissue lesions and skeletal retardation.