Plasticisers health effects

The Department of Health is reported to be searching for diethylhexyl phthalate-free products for the National Health Service following international concern over possible health effects from exposure to the plasticiser. The EU Scientific Committee on Medicinal Products Medical Devices has made no recommendation that hospitals should take any precautionary measures to reduce exposures of groups of patients considered to be at risk although Health Canada and the FDA have issued precautionary assessments. 

The European Union is poised to announce that phthalate plasticisers pose no risk to either human health or to the environment. A five-year risk assessment into six phthalates, which are used extensively in PVC products, is nearing an end. In September, an EU Technical Meeting completed its assessments of DINP and DIDP and decided that the two needed no classification or labelling for environmental or health effects. DINP is the phthalate most often used in soft PVC toys and items intended to be put into childrens mouths, on which most of the recent anti-PVC furore has been focused. 

The most common phthalate plasticisers are di-2-ethyl hexyl phthalate (DEHP), di-isodecyl phthalate (DIDP), and di-isononyl phthalate (DINP). Phthalate use has been controversial for years becanse of its snspected health hazards, especially in the case of DEEIP. In both wildlife and laboratory animals, phthalates have been linked to a range of reproductive health effects, with claims that most of them can function as an endocrine disrupting chemical (EDC), and also as cancer-causing agents (specifically in the liver and kidneys). Snch negative effects that phthalates are suspected to have on health have been attribnted to short ester chains (< C9). In fact, phthalates are already distributed worldwide in the environment. Some phthalates are even found in deep-sea jellyfish 1,000 meters below the surface of the North Atlantic Ocean. A number of studies have shown that most people are probably contaminated by substantial quantities of these chemicals, and yet for hnmans, no safe level of exposure to phthalates has been determined. There are also claims about the leaching of certain phthalate plasticisers from biomedical plastics (e.g., intravenous tubes) and hence directly into the patients bloodstream. In one snch stndy, it was shown that about 60% of the DEHP/DOP had migrated to the patient, while almost all of the bis (2-ethylhexyl) adipate (DOA) has been retained in the tnbe [28]. 

There are further examples of the possible health effects of plasticisers and additives used in PVC ... 

For additional information about plasticisers and their possible health effects, please see Chapter 3. 

Chlorinated paraffins (mainly CPVC) are widely used in PVC to have greater resistance to ignition and combustion than general purpose plasticisers. However, the effects of chloroparaffins on health is still a controversial issue and their use as flame retarders in PVC applications for cables, wall coverings and flooring are declining [23]. For more information and health effects of stabilisers, flame-retarders, please see Chapter 3. 

C. E. Koop, A Scientific Evaluation of Health Effects of Two Plasticisers Used in Medical Devices and Toys A Report from the American Council on Science and Health, 1999, http /Avww.medscape.com/pages/public/about/about. 

Health effects of PVC itself and its additives (mainly plasticisers) have been the subject of a very intense debate for many years, beginning from the danger of release or extraction of the heavy metal based stabilisers and health implications of phthalate plasticisers and other additives to the danger of formation of dioxins and hydrogen chloride gas during accidental fires . For many years, there has been a never ending debate between different parties about PVC and its effect on health and on the environment, some are... 

For over 20 years there has been a continued debate on the potentially negative environmental and health effects of phthalate based plasticisers. Phthalates are diesters of phthalic acid anhydride and alcohols. The most... 

As mentioned previously, the EU put forward the year 2002 as the key milestone to complete phthalates risk assessment, although this wasn t actually achieved. Currently, it is known that there is a high interest in plasticisers and their effects on health worldwide, and that in the EU, about one million Euro a year is being spent on such research in industry. 

As briefly discussed previously, PCB, a family of highly toxic and oily, non-flammable industrial chemicals, can exist at high levels in and around some old buildings due to the sealants based on polysulfide polymers containing PCB. PCB in many polysulfide sealants have been replaced now by chlorinated paraffins, and smaller volumes of chloroparaffins are used as plasticising agents for various sealants. However, the effects of chloroparaffins on health, is also a controversial issue, and its use in sealants is in decline. In sealants, especially in polysulfide and PU sealants, the BBP is also used. 

In fact the European Union has now cleared DEHP fiom any association with harm to public health, on the grounds that exposure levels are at least 700 times lower than the current safe levels. Discussions continue in relation to the other two major phthalate plasticisers, DINP and DIDP. Benzyl butyl phthalate rates Category 2 for adverse fertihty effects, but only Category 3 for its effects on human development. 

For more detailed information about certain plastics and plasticisers and their effects on health, please see Section 12.2.2.1 [Thermoplastic construction materials (polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), polyethylene (PE) and polycarbonate (PC)] and the plasticisers part of Section 12.2.2.1 (Additives). 

Impact Modifiers Impact modifiers are either systems with spherical elastomer particles in a rigid polymer matrix or they are systems with a honeycomb, network type of dispersed elastomeric phase. For the spherical elastomeric particles, examples are acrylonitrile butadiene styrene (ABS), methacrylate-butadiene-styrene (MBS) and acrylics. These systems are either graft copolymers of methyl methacrylate-butyl acrylate-styrene or methyl methacrylate-ethylhexyl acrylate-styrene. For the honeycomb, network type of dispersed elastomeric phase ethylene vinyl acetate (EVA) and chlorinated polyethylene (CPE) or directly dispersed rubber are examples. Both of these two impact modifiers exist in the polymeric form, hence they can hardly migrate and evaporate because of their size. As a result, they pose almost no problems to health. For PVC window frame production, usually the first type (and acrylic impact modifiers) are used while MBS modifiers are found to be very effective in plasticised as well as in rigid PVC. CPE is mainly used in PVC for products like sheet, pipe, gutters and sidings. 

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