The materials used in pet products, cars, toys and other products, including plastics, paints, and fabrics are made up of chemicals, and may also contain added chemicals to impart specific properties such as rigidity, durability, flexibility or flame resistance.
When children and pets put these products into their mouths, some of these chemicals may enter their bodies. Some of the substances, which are not always chemically bound to the products, may also be released directly onto skin or into the air that children and pets breathe. However, the detection of a chemical in a product does not necessarily mean there is direct exposure.
The chemicals detailed below have been identified by regulatory agencies as problematic because of their toxicity or suspected toxicity, persistence, and/or their tendency to build up in people and the environment. These chemicals and compounds have also been linked in animal and, less often, in human studies to long-term health impacts such as birth defects, impaired learning, liver toxicity, and cancer.
Each of us is exposed to toxic chemicals from many sources, ranging from our cars to toys, and it is the combination of these many exposures that is of greatest concern. Each of these chemicals also represents potential exposure to workers or communities during the manufacture of products containing them, and potentially to communities where the products are disposed.
These chemicals are of particular danger to children and pets. Children’s growing and developing bodies are more vulnerable to the effects of toxic chemicals, and pets spend a lot of time on the floor and furniture, with cats especially cleaning their fur and swallowing chemicals on their bodies.
The rapid screening technology used for HealthyStuff.org cannot identify the presence and concentration of every chemical of concern. For example, a chemical of concern like Bisphenol A cannot be detected by the XRF device.
HealthyStuff.org ratings do not provide a measure of health risk or chemical exposure associated with any product, or any individual element or related chemical. Our ratings only provide a relative measure of high, medium, and low concentrations of several hazardous chemicals or chemical elements in a toy or children's product in comparison to criteria established in the methodology.
What it is and where it’s found: Antimony (Sb) is a metalloid chemical element found naturally in minerals at low concentrations. Antimony is used in a number of industries, including the production of batteries and other metal alloys. In consumer products, antimony might be found in plastic materials, polymers, or items with flame retardants.
Health effects: Antimony trioxide is classified as a carcinogen in the state of California and has been listed as a possible human carcinogen by the International Agency for Research on Cancer and the European Union. In long-term studies, animals that breathed very low levels of antimony had eye irritation, hair loss, lung damage, and heart problems, and higher levels have been shown to cause fertility problems and lung cancer in animals (ATSDR 1995).
What it is and where it’s found: Arsenic (As) is a metalloid element that is naturally present in both organic and inorganic forms. Inorganic arsenic is a naturally-occurring groundwater contaminant in some geographical regions and can also be used as a wood preservative. Arsenic is used as an alloying agent, and industrial uses range from the production of feed additives, fertilizers, herbicides, and insecticides to processing of materials like glass, paper, and textiles (ATSDR 2007, WHO 2016). Organic arsenic can be converted to the more toxic inorganic form when it is ingested and also can be found in seafood or food grown using contaminated groundwater (WHO 2016).
Health effects:The effects of inorganic arsenic, which is more toxic than organic arsenic, depends on level and route of exposure. Inorganic arsenic is a known human carcinogen, with there being strong evidence linking arsenic to lung, skin, and bladder cancer (ATSDR 2007, Celik 2008). Inorganic arsenic may also cause skin irritation, skin color changes, blood disorders, cardiovascular diseases, and hormone disruption (ATSDR 2007). Preliminary data suggest that inorganic arsenic may interfere with normal fetal development (Vahter 2009) and cause deficits in brain development and intelligence (Wasserman 2004), and other studies have implied that drinking low levels of arsenic may lead to type 2 diabetes (Navas-Acien 2008).
Bisphenol A and other Bisphenols
What it is and where it’s found: Bisphenol A (BPA) is a synthetic compound produced for use in plastics and epoxy resins and coatings. BPA is employed in a wide range of consumer goods, and is used to make plastics clear, strong, and rigid. It is also a precursor for epoxy resins used in food cans and many other applications. BPA is absorbed readily by the body, and most exposure occurs through consumption and BPA can also be absorbed through the skin. BPA is so ubiquitous that although it is eliminated by the body relatively quickly, it is always present in the body (NIEHS 2016). Bisphenol S (BPS) is a synthetic compound used in plastics and resin and coatings. BPS is found in many consumer goods, including plastics, food packaging, receipt paper, and industrial applications.
Health effects: While the status of BPA as an endocrine-disrupting chemical is well-supported in research, BPS has received little investigation on its effects on the human body. Despite the more lax regulation on the use of BPS, the chemical similarity of BPA and BPS and new research suggest that BPS may be just as active in the body as an endocrine -disruptor (Rochester and Bolden 2015).
What it is and where it’s found: Cadmium (Cd) metal is used in production of many electronic devices, as a stabilizer in polyvinyl chloride (PVC). Burning of fossil fuels, metal refining and smelting, and other industrial processes release cadmium compounds into the environment (Environment and Climate Change Canada 2013).
Health effects: Cadmium can cause adverse effects on the kidney, lung and intestines (ATSDR 2012). It is classified as a known human carcinogen, associated with lung and prostate cancer (ATSDR 2012). Cadmium exposure is associated in animal studies with developmental effects, including possible decreases in birth weight, delayed sensory-motor development, hormonal effects, and altered behavior (Schantz 2001). Exposure to cadmium can result in bone loss and increased blood pressure (Arora et al. 2009).
What it is and where it’s found: Lead (Pb) is a heavy metal element that is found naturally and produced by mining ore. Lead has a long history of use in production of various materials, and continues to be used in a wide variety of consumer products. Indirect sources of lead also include burning fossil fuels and manufacturing. Metal and electronic products and devices are often produced with lead. Lead-containing pigments used to be very common in plastics. Lead was used as a stabilizer in paint until the late 1970s in the U.S., leading to widespread and ongoing lead exposure of children from lead-tainted dust and paint chips in these homes. Lead remains common as a stabilizer in PVC coatings on electrical wires. Lead was relatively common in children's products and toys until the Consumer Product Safety Commission mandated a limit of 100 ppm total lead in 2011.
Health effects: Scientists have found there is no safe level of lead for children - even the smallest amount affects a child's ability to learn (Lanphear et al. 2005, Gilbert 2006). Children are more vulnerable than adults to lead (ATSDR 2007). Lead impacts brain development, causing learning and developmental problems including decreased IQ scores, shorter attention spans, and delayed learning (Gilbert 2004). When children are exposed to lead, the developmental and nervous system consequences are irreversible (Gilbert 2006). Nationwide, 310,000 children already have lead levels of concern (ATSDR 2007).
What it is and where it’s found: Mercury (Hg) is a metallic element. Inorganic compounds containing mercury are often used in inks, adhesives, and as a catalyst in reactions to form polyurethanes (ATSDR 2011). Mercury can exist in a variety of compounds, and some forms are more toxic than others.
Health effects: Mercury is a persistent toxic chemical that can build up in the body. All forms of mercury can affect the kidneys. Organic, inorganic, and metallic mercury are toxic to the nervous system, each affecting different regions of the brain. Young children are more sensitive to mercury and may be exposed to mercury via the mother’s body to the fetus or through breast milk (ATSDR 2011).
What are they: Ortho-phthalates (pronounced "thal-ates") are a group of industrial chemicals used as plasticizers that add flexibility and resilience to many plastic consumer products. Ortho-phthalates are referred to generally as phthalates. Many phthalate compounds exist, with slight chemical differences. Some of the common phthalates found in consumer products are:
- Bis(2-ethylhexyl)phthalate (DEHP)
- Dimethyl phthalate (DMP)
- Di-n-butyl phthalate (DBP)
- Diethyl phthalate (DEP)
- Diisononyl phthalate (DINP)
- Diisobutyl phthalate (DIBP)
- Di-n-octylphthalate (DNOP)
DEHP and BBP are primarily used as plasticizers in PVC-based plastics, as well as other flexible plastics. They may be found in tablecloths, furniture, vinyl flooring, shower curtains, wallpapers, garden hoses, automobile upholstery and tops, medical tubing, and blood storage bags. DEP and DBP are used in non-plastic consumer items as fixatives, detergents, lubricating oils, and solvents. The chemicals can also be found in carpets, paints, glue, insect repellents, time release capsules, and personal care products such as soap, shampoo, hair spray, nail polish, deodorants, and fragrances.
Although many individual phthalate compounds may be found in different products, in our studies we often report "phthalates" as a single entity. Different phthalate compounds are chemically very similar, and work by HealthyStuff has shown that manufacturers introduce new phthalates periodically.
Where do they end up? Phthalate plasticizers can leach or migrate into foodstuffs and other materials they are in contact with, and cling to dust, which may become airborne. Consumer products containing phthalates can result in human exposure through direct contact and use, indirectly through transfer onto other products, and through ingestion or inhalation via dust. Although certain phthalates have been restricted in children’s products since 2008, phthalates remain a ubiquitous part of the human body burden of chemicals.
Although phthalates do not all have identical effects in the human body, the structural similarity of phthalate compounds lead us to treat the whole class of ortho-phthalates as suspects in a range of negative health impacts (CPSC 2015).
Polyvinyl chloride and other plasticizers
What it is and where it’s found: PVC (polyvinyl chloride), otherwise known as vinyl, is a widely used plastic that presents environmental and health hazards during all phases of its life cycle – production, use and disposal. During the production phase, workers at PVC facilities, as well as residents in surrounding areas, may be exposed to vinyl chloride (a building block of PVC) and/or dioxin (an unwanted byproduct of PVC production), both of which are carcinogens. At the end of a product's life, PVC can create dioxin when burned. PVC is not easily recycled.
Because pure PVC is brittle, it requires added plasticizers to make it flexible and to impart other desired properties. A group of plasticizers commonly found in PVC products are phthalates. Over 90% of phthalates produced globally are used in PVC products. Lead and other heavy metals were commonly used in the past as stabilizers for PVC plastic (WTC 2009), especially in electrical wire insulation, and are still sometimes used in that capacity.
A number of non-phthalate plasticizers are used as alternatives in flexible PVC. These include
- dioctyl terephthalate (DOTP) also called bis(2-ethylhexyl) terephthalate (DEHT)
- dibenzoate esters, including those with trade name Benzoflex
- acetyl tributyl citrate (ATBC)
- adipates such as bis(2-ethylhexyl) adipate (DEHA)
- tris(2-ethylhexyl) trimellitate (TOTM)
- epoxidized soybean oil
- diisononyl cyclohexane-1,2-dicarboxylate (DINCH)
High Definition X-ray Fluorescence (HD XRF) is used to detect chlorine, the element, in products. For chlorine we consider results above 1,000 ppm to be at least semi-quantitative. While XRF testing cannot identify molecular structure of organic chemicals, detecting chlorine greater than 3,500 ppm in certain matrices has been successfully used to infer the presence of chlorinated flame retardants. Detection of chlorine greater than 5% (50,000 ppm) suggests the possible presence of PVC polymer, which we can determine through FTIR spectroscopy.
What it is and where it’s found: Tin (Sn) is a metal element used as a metal alloy or in the form of organotin compounds. Tin is used as an alloy to create bronze and pewter, and is also used as plating on metals like steel. Organotins are used as stabilizers in PVC products, particularly in rigid PVC products (Modern Plastics Handbook 2000). They are also used as catalysts in silicone production. Organic tin compounds are often used to stabilize PVC plastic and are more likely to be present in children's toys, or as pesticides (Modern Plastics Handbook 2000).
Health effects: Organic forms, known as organotins, are believed to be toxic at lower levels of exposure. Several tin compounds cause nervous system harm, including tributyl tin, dibutyl tin, trimethyl tin, and dimethyl tin (Cooke 2004, Jenkins 2004, ASTRD).The developing brain is particularly vulnerable. Dibutyl tin is toxic to nervous system cells at concentrations similar to those found in people today (Jenkins 2004). Some forms of organotin, like tributyl tin and dibutyl tin, are also toxic to the immune system (Cooke 2004).
Sources and further reading
Arora, M., Weuve, J., Schwartz, J. & Wright, R. O. Association of environmental cadmium exposure with periodontal disease in U.S. adults. Environ. Health Perspect. 117, 739–744 (2009).
ATSDR. ToxFAQs™ for Antimony. Toxic Substances Portal (1995).
ATSDR. ToxGuide for Arsenic. (Center for Disease Control and Prevention, 2007).
ATSDR. Toxicological Profile for Cadmium. Toxic Substances Portal (2012).
ATSDR. Toxicological Profile for Lead. Toxic Substances Portal (2007).
ATSDR. Toxicological Profile for Mercury. Toxic Substances Portal (2011).
ATSDR. Toxicological Profile for Tin. Toxic Substances Portal (2011).
Celik, I. et al. Arsenic in drinking water and lung cancer: A systematic review. Environ. Res. 108, 48–55 (2008).
Choe, S.Y. et al. Evaluation of estrogenicity of major heavy metals. Science of the Total Environment 312, 15–21 (2003).
CPSC. Phthalates. U.S. Consumer Product Safety Commission (2015).
El Shanawany, S. et al. The potential DNA toxic changes among workers exposed to antimony trioxide. Environ Sci Pollut Res Int. 24(13), 12455 (2017).
Environment and Climate Change Canada. Inorganic cadmium compounds. Environment and Climate Change Canada (2013).
Gilbert, S. G. A small dose of toxicology: the health effects of common chemicals. (CRC Press, 2004).
Gilbert, S. G. & Weiss, B. A rationale for lowering the blood lead action level from 10 to 2 μg/dL. Neurotoxicology 27, 693–701 (2006).
Harper, C. A. Modern plastics handbook. (McGraw-Hill, 2000).
Jenkins, S. M., Ehman, K. & Barone, S. Structure-activity comparison of organotin species: Dibutyltin is a developmental neurotoxicant in vitro and in vivo. Dev. Brain Res. 151, 1–12 (2004).
Lanphear, B. P. et al. Low-level environmental lead exposure and children’s intellectual function: An international pooled analysis. Environ. Health Perspect. 113, 894–899 (2005).
Navas-Acien, A., Silbergeld, E. K., Pastor-Barriuso, R. & Guallar, E. Arsenic exposure and prevalence of type 2 diabetes in US adults. J. Am. Med. Assoc. 300, 814–822 (2008).
Niedzwiecki, M. M. et al. A dose-response study of arsenic exposure and global methylation of peripheral blood mononuclear cell DNA in Bangladeshi adults. Environ. Health Perspect. 121, 1306–1312 (2013).
NIEHS. Bisphenol A (BPA). National Institute of Environmental Health Sciences (2016).
Rochester, J. R. & Bolden, A. L. Bisphenol S and F: A Systematic Review and Comparison of the Hormonal Activity of Bisphenol A Substitutes. Environ. Health Perspect. 123, 643–650 (2015).
Schantz, S. L. & Widholm, J. J. Cognitive effects of endocrine-disrupting chemicals in animals. Environ. Health Perspect. 109, 1197–1206 (2001).
Tarragó, O. Lead Toxicity. ATSDR Case Stud. Environ. Med. 1–63 (2007).
Tucker, P. G. Cadmium Toxicity. ATSDR Case Stud. Environ. Med. 1–63 (2008).
Vahter, M. Effects of arsenic on maternal and fetal health. Annu. Rev. Nutr. 29, 381–399 (2009).
WHO. Arsenic: Fact Sheet. (World Health Organization, 2006).
Zhu, L. et al. Exposure Assessment of Sb2O3 in PET Food Contact Materials. Biomedical and Environmental Sciences 29(4), 305-313 (2016).