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Plasticisers: An Update. David Cadogan Plasttekniske Dager Oslo, 8-9 November 2006. Outline. ECPI Plasticiser requirements Are phthalates a threat to human health Legislative actions Classification and labelling Risk assessments Toys, food contact materials, medical devices Reach
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Plasticisers: An Update David Cadogan Plasttekniske Dager Oslo, 8-9 November 2006
Outline • ECPI • Plasticiser requirements • Are phthalates a threat to human health • Legislative actions • Classification and labelling • Risk assessments • Toys, food contact materials, medical devices • Reach • Market trends • Summary
ECPI • European Council for Plasticisers and Intermediates • A Sector Group of CEFIC – the European Chemical Industry Council • European producers of plasticisers, alcohols and acids • Sponsorship of scientific studies by independent experts • Provide users, legislators and other interested bodies with information on safety, health and the environment • Close liaison with trade organisations in USA and Japan
Plasticiser requirements • Compatible with PVC • Efficient • Ease of processing • Low volatility • Low migration/extraction • Flexibility at low temperatures • High temperature performance • Electrical resistance
93% of Plasticisers are Phthalates • Phthalates have : • Optimum balance of polar / non-polar groups • Best all round performance / price ratio DEHP • Performance can be fine tuned by using appropriate alcohol C4 - C7 alcohol : Lower viscosity, faster processing C8 – C10 alcohols : General purpose C11-C13 alcohols : High temperature performance >80% linear : Better low / high temperature performance
93% of Plasticisers are Phthalates More polar groups – Increased compatibility with PVC and easier processing BBP – Fast processing and stain resistance BBP
Potential Health Impact - Carcinogenicity • 1982 – Liver tumours in rodents caused IARC to classify DEHP as “possibly carcinogenic to humans” 18 years of research showed : • Phthalates, hypolipidaemic drugs and other chemicals cause tumours in rodents by peroxisome proliferation (PP) • No PP or liver damage in monkeys fed DEHP and DINP • No PP or liver damage in humans taking hypolipidaemic drugs • No DEHP induced liver tumours in mice lacking PP receptor • 2000 - IARC Reclassified DEHP - Phthalate induced liver cancer in rats and mice is not relevant to humans
Potential Health Impact - Reproductive Effects • High levels of some phthalates produce testicular atrophy in rodents • Little, if any, effects seen with DMP, DEP, DINP and DIDP • Levels can be defined at which no effects occur (NOAEL) • In general NOAELs are orders of magnitude higher than levels of exposure. Therefore no risk • Studies ongoing to identify the mechanism underlying the reproductive effects in rodents – are they relevant to humans?
Adverse Effects on Human Health The facts are: • No evidence of any phthalate having an adverse effect on human health • 20 year follow-up study on 242 low birth weight individuals (high DEHP exposure in intensive care) showed no effects on male fertility • Adolescents exposed to DEHP via ECMO as neonates show no adverse effects on growth or sexual maturity • Adverse effects are only seen in rodent studies • Adverse effects not seen in non-human primates However - There are now two studies claiming to see effects in humans
Baby Boys Feminised by Prenatal Phthalate Exposure - Claims • Swan et al. (August 2005) measured Anogenital Index (AGI) in 85 boys aged between 2 and 36 months. (AGI = AGD / Weight). • Smaller AGI in boys said to correlate with higher levels of metabolites of DEP, DBP, DIBP and BBP in mothers urine during pregnancy • AGI is smaller in females than in males hence these phthalates are said to have a feminising effect • Highly publicised – press conference more important than peer review.
Prenatal Phthalates Feminise Baby Boys – The Facts Inadequate measurement of maternal phthalate exposure • Only one urine sample taken during pregnancy • Studies by Hauser et al (2004) and Hoppin et al (2002) indicate that repeated urine measurements are necessary to determine exposure Concerns re measurement of AGD in boys • Poor planning. AGD changes rapidly with age but they measured at ages ranging from 2 – 36 months. Hence needed extensive regression analysis • The only other study (Salazar-Martinez et al, 2004) was systematic - 45 boys measured at 6 hours old. No regression needed – apparently less variation in AGD / weight
Prenatal Phthalates Feminise Baby Boys – The Facts Authors attempt to make case stronger than it is • Independent statisticians find the conclusions are unsound • US National Toxicology Programme panel of 11 toxicologists have concluded that the findings are not reliable • No correlation between AGI and primary metabolite of DEHP in mother’s urine but weak correlation with the level of secondary metabolites - not logical • Strong correlation with MEP in urine – contrary to many other studies on DEP
Phthalates in Breast Milk Effect Baby Boys - Claims • Main et al. (February 2006) measured levels of phthalate monoesters in breast milk of 130 mothers of baby boys at 1-3 months postnatally. • Subjects selected so that approximately half of the boys had undescended testes. • No correlation found between undescended testes and monoesters in breast milk – main aim of the study but gets little mention in the report • Measured levels of reproductive hormones in boys at three months and investigated link with levels of phthalate monoesters in breast milk. • A link is proposed between levels of some phthalate metabolites in breast milk and some hormone levels in male offspring
Phthalates in Breast Milk Effect Baby Boys – The Facts Statistical treatment of data and interpretation of results questioned • Independent statisticians agree that there is no real correlation. • The authors discount results which do not fit their hypothesis as being “random findings” • The lack of a link between MEHP and hormone levels is said to be due to the “limited number of samples in the study” • Study rejected by EU Member States Experts in DEHP Risk Assessment • US Expert Panel on Human Reproduction believes that some hormone measurements are not relevant and breast milk samples are most likely contaminated
Legislative Actions • Classification and labelling of dangerous substances • Existing substances legislation – Risk assessment and management • Toys and childcare articles • Food contact materials • Medical devices • REACH
Hazard - Classification and Labelling • Category 1 Substances known to cause effects in humans. Based on epidemiological data. • Category 2 Substances to be regarded as if they cause effects in humans. Based on clear evidence in animal studies. • Category 3 Substances causing concern for humans. Based on less convincing evidence in animal studies. Classification and labelling does not apply to articles Aim – To ensure safe handling and use in the workplace
Classification and Labelling Backbone Fertility Developmental DMP 1 None None DEP 2 None None DPrP 3 None None DIBP SCL = 25% 3 Cat 3 Cat 2 DBP 4 Cat 3 Cat 2 DPP 4 - 5 Cat 2 Cat 2 BBP 4 - 7 Cat 3 Cat 2 DIHP 5 - 6 None Cat 2 DEHP 6 Cat 2 Cat 2 711P (Branched) 5 - 9 Cat 3 Cat 2 DINP 7 - 8 None None DIDP 8 - 9 None None 79P (Linear) 7 - 9 None None 911P (Linear) 9 - 11 None None
Existing Substances Legislation Council Regulation EEC / 793 / 93 on the evaluation and control of the risks of existing substances • To properly assess the risks imparted by all chemicals • To both humans and the environment • Margin of Safety (MOS) = NOAEL / Exposure • MOS > 100 = No Risk • To identify risk management requirements if necessary and implement a Risk Reduction Strategy
DBP, DINP, DIDPRisk Assessments / Reduction • Risk Assessments and Risk Reduction Strategies published in Official Journal on 13 April 2006 Human health risks: • DBP – No consumer risks including cosmetics. Risk to workers assuming worst case exposure – OEL to be implemented • DIDP – Theoretical risks for children via toys – Toy legislation • DINP – No risks in any current use – Toy legislation due to difference of opinion between RAR and CSTEE Environmental risks: • DBP – Possible risk to vegetation near some processing plants - Extra monitoring data on exhaust air • DINP and DIDP – No risks
DINP & DIDP Risk Assessments / Risk Reduction • Two versatile high volume phthalates • Finally perceived as being “Risk Free” following revision of legislation for use in toys • For both health and environmental effects • Can be used in all applications except toys and childcare articles “which can be put in the mouth” • Not hazardous - not classified CMR or Dangerous to the Environment • Large shift in consumption to DINP and DIDP
BBP & DEHP Risk Assessments / Risk Reduction • Risk assessments to be completed via “written procedure” during Q4 2006. Publication in 2006 / 2007 Human health risks: BBP – few, if any, risks anticipated – Consumption falling rapidly DEHP • Workers – OEL to be defined and implemented • Children via toys – New legislation • Haemodialysis and long term transfusion in children / neonates - Requested opinion of expert medical committee • Possibly children living near some processing plants – Agree Marketing and Use Directive to control DEHP emissions
Risk Assessments / Risk Reduction Environmental risks: • BBP – Possible risk to water and sediment near processing plants - Fish study and processing plant emission data • DEHP –Risks only seen for default emission levels from hypothetical plants. No risks when using real emission data which are 1000 times lower. • General population via the environment - Kemi wanted to ban DEHP in all outdoor applications. Commission not convinced – no risk identified. • Biomonitoring more than 3.000 people - shows no risks to man at regional level (MOS range from 280 to 1700)
Toys and Childcare Articles • Permanent measures published in the Official Journal on 27 December 2005 • DBP, BBP and DEHP banned in all toys and childcare articles • DINP, DIDP and DNOP banned in toys and childcare articles which can be put in the mouth • National legislation to be enacted from 16 January 2007 • Entirely political decision ignoring science based risk assessments • A range of alternative plasticisers available – citrates, etc.
Food Contact Materials • New legislation is expected to come into force in the EU during Q4 2006 • EFSA Scientific Panel has re-examined the phthalate toxicity data and published TDI values. • Concluded that phthalates may be used in a variety of repeat and single use food contact applications • DEHA and polymeric plasticisers will continue to be used in a wide range of food contact applications, especially clingfilm
Medical Applications • DEHP Risk Assessment identifies risks to patients (MOS < 100) via : • Long term haemodialysis (adults) • Transfusions (neonates) • Long term blood transfusion (children) (Lowest MOS via IV = 800) • It is possible that these three applications will move from DEHP to alternatives such as ATBC, DINCH, trimellitates, acetylated glycerol esters or polymeric plasticisers. • However this sector is conservative and reluctant to change away from plasticisers which have given no adverse effects in patients • Threats from activists (HCWH) and from other polymers continue but it is difficult to match the cost / performance characteristics of PVC
Medical Applications • SCMPMD Opinion of September 2002 concluded that no specific recommendation could be made to limit the use of DEHP • We must await the Opinion of the new Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) – February 2006 • However the attacks continue: • EU Parliament Environment Committee (w/c 2nd October) agreed an amendment to the Medical Devices Directive prohibiting the use of CMR substances in medical devices. This still has to be voted on in plenary • Many drugs are CMR but are used on a risk/benefit basis • This amendment is based on hazard – there may be little exposure and hence no risk
Phthalate Alternatives Confer Special Properties • Adipates – Low temperature flexibility - food and medical • Polyesters – Low migration into oil, etc - food and medical • Trimellitates – High temperature cable sheathing • Citrates – PVdC film, some medical – Some adverse human reactions • Benzoates – Easy processing like BBP • Phosphates – Fire resistance • Alkyl sulphonates – Easy processing, weather resistance • DINCH – Possible use in medical and food contact – EFSA approval • Acetylated glycerol esters – Food contact
REACH – Registration, Evaluation and Authorisation of Chemicals
Impact of REACH on Plasticisers • The commonly used plasticisers are data-rich and have been subjected to various risk assessments so no problems regarding registration. • CMR substances will be subject to authorisation to allow them to be used in each application. • We have the risk assessment data but will it be accepted or will substitution be demanded ? • Some Member States may propose that even those phthalates which are not classified as CMR should be subject to authorisation because they give rise to an “equivalent level of concern” • Environment Committee (10th October) voted to increase pressure for substitution and reduce level of scientific evidence needed to prove that a substance is of “equivalent concern”
Western Europe Plasticiser Consumption (‘000s of tons) Source: ECPI, 2006
European Plasticiser Consumption - Trends 1999 2005 Source: ECPI, 2006
Plasticisers – The Way Forward • The family of phthalates satisfy the performance, health and safety requirements of the vast majority of applications. • Classification, labelling and risk assessment has resulted in a move to DINP and DIDP and a decrease in DEHP, DBP and BBP consumption • Alternatives to phthalates already exist or are being developed for certain applications • Food contact materials, medical devices, toys and childcare articles • Low migrating plasticisers – polymerics and trimellitates • Lower animal toxicity – adipates, citrates, terephthalates, DINCH, acetylated glycerol esters
Summary • Phthalates and speciality esters meet the needs of all PVC applications • Increase in DINP and DIDP use due to positive risk assessments • Decrease in DEHP, DBP and BBP due to Hazard Classification • Health effects not seen in primates - only in rodent studies • No human cancer concern. Investigating relevance to humans of rodent reproductive effects • High profile human toxicological studies are not based on sound science • Biomonitoring data very helpful in risk assessment and risk reduction • There will be moves to new plasticisers due to new legislation and concerns regarding toys, food contact and medical devices • There is still a very strong future for flexible PVC