Phthalates
Lower-molecular-weight phthalates are typically replaced in many products in the United States, Canada, and European Union over health concerns.
In many countries, DEHP is regulated as a toxin, and is banned from use in broad categories of consumer goods, such as cosmetics, children's toys, medical devices, and food packaging.
[14] Phthalates derived from alcohols with 7-13 carbon atoms occupy a privileged position as general purpose plasticizers, suitable for almost all flexible PVC applications.
Compounds derived from alcohols with 1-3 carbon atoms are not used as plasticizers in PVC at all, due excessive fuming at processing temperatures (typically 180-210 °C).
[14] Historically DINP, DEHP, BBP, DBP, and DIHP have been the most important phthalates, however many of these are now facing regulatory pressure and gradual phase-outs.
[citation needed] Other plasticised polymer systems include polyvinyl butyral (particularly the forms used to make laminated glass), PVA and its co-polymers like PVCA.
The great advantage offered by these esters is that they are phlegmatizers, i.e. they minimize the explosive tendencies of a family of chemical compounds that otherwise are potentially dangerous to handle.
[citation needed] Relatively minor amounts of some phthalates find use in personal-care items such as eye shadow, moisturizer, nail polish, liquid soap, and hair spray.
[26] and species of mosquitoes such as Anopheles stephensi, Culex pipiens and Aedes aegypti,[27][28][29] Diallyl phthalate is used to prepare vinyl ester resins with good electrical insulation properties.
[citation needed] The mechanism by which phthalates and related compounds plasticize polar polymers has been a subject of intense study since the 1960s.
[citation needed] Being inexpensive, nontoxic (in an acute sense), colorless, noncorrosive, biodegradable, and with easily tuned physical properties, phthalate esters are nearly ideal plasticizers.
Since alternative plasticizers such as DEHT and DINCH are more likely to bind to organic matter and airborne particles indoors, exposure occurs primarily through food consumption and contact with dust.
The same study found that DEHP, BBzP, and DnOP were in significantly higher concentrations in dust samples collected in homes where polishing agents were used.
Although they did not examine health outcomes, they noted that "Young infants are more vulnerable to the potential adverse effects of phthalates given their increased dosage per unit body surface area, metabolic capabilities, and developing endocrine and reproductive systems.
The Food and Drug Administration did an extensive risk assessment of phthalates in the medical setting and found that neonates may be exposed to five times greater than the allowed daily tolerable intake.
This finding led to the conclusion by the FDA that, "[c]hildren undergoing certain medical procedures may represent a population at increased risk for the effects of DEHP".
[40] In 2008, the Danish Environmental Protection Agency (EPA) found a variety of phthalates in erasers and warned of health risks when children regularly suck and chew on them.
[38] One study, conducted between 2003 and 2010 analysing data from 9,000 individuals, found that those who reported that they had eaten at a fast food restaurant had much higher levels of two separate phthalates—DEHP and DiNP—in their urine samples.
[50][51] Biosynthesis is believed to involve a modified Shikimate pathway[52][53] The extent of this natural production is not fully known, but it may create a background of phthalate pollution.
[54] Phthalates are under research as a class of possible endocrine disruptors, substances that may interfere with normal hormonal responses in varied environmental conditions.
[58] A 2024 review indicated that exposure of mothers to environmental phthalates may have adverse pregnancy outcomes, such as a higher miscarriage rate and lower birth weights.
[61] A 2018 study indicated that exposure to phthalates during developmental stages in childhood may negatively affect adipose tissue function and metabolic homeostasis, possibly increasing the risk of obesity.
[62] The governments of Australia, New Zealand, Canada, the US, and California have determined that many phthalates are not harmful to human health or the environment in amounts typically found, and therefore are legally unregulated.
[69] In 1999, DEHP was put on the national List of Toxic Substances, under the Canadian Environmental Protection Act, 1999, and in 2021, it was deemed a risk to the environment.
[70] Twenty of the 28 phthalate substances under national screening programs are considered possible risks to human health or the environment.
[citation needed] Generally, the high molecular weight phthalates DINP, DIDP, and DPHP have been registered under REACH and have demonstrated their safety for use in current applications.
[68][72] The creation of an Annex XV dossier, which could ban the import of products containing these chemicals, was being prepared jointly by the ECHA and Danish authorities, and expected to be submitted by April 2016.
[68] During August 2008, the United States Congress passed and President George W. Bush signed the Consumer Product Safety Improvement Act (CPSIA), which became public law 110–314.
The California Office of Environmental Health Hazard Assessment, charged with maintaining the Proposition 65 list and enforcing its provisions, has implemented a "No Significant Risk Level" of 146 μg/day for DINP.
The Occupational Safety and Health Administration stated that the maximum amount of diethyl phthalate allowed in workroom air during an 8-hour workday, 40-hour workweek, is 5 milligrams per cubic meter.
