Applicability of an on-line solid-phase extraction liquid chromatography - tandem mass spectrometry for the wastewater-based assessment of human exposure to chemicals from personal care and household products.

Wastewater-based epidemiology (WBE) can be a useful complementary approach to assess human exposure to potentially harmful chemicals, including those from personal care and household products. In this work, a fully automated multiresidue method, based on on-line solid-phase extraction liquid chromatography - tandem mass spectrometry, was developed for the determination of 27 biomarkers of human exposure to selected chemicals from personal care and household products, including parabens, UV filters, phthalates and alternative plasticizers, phosphorous flame retardants/plasticizers (PFRs), and bisphenols. These biomarkers include both the parent compounds and their human metabolites. In addition, two oxidative stress biomarkers, 8-epi-prostaglandin F2α and 4-hydroxy nonenal mercapturic acid, were also considered in the study. The method was carefully optimized to tackle the challenges of analyzing compounds with different physico-chemical properties in a highly complex raw wastewater matrix, while model experiments were performed to investigate filtration losses and analyte stability. The applicability of the developed method was tested by analyzing raw wastewater from four European cities: Antwerp, Brussels (Belgium), Girona (Spain), and Zagreb (Croatia). Twenty-one biomarkers (10 parent compounds and 11 metabolites) were detected in all analyzed wastewater samples. The parent compounds with the highest mass loads were PFRs, parabens, and bisphenol S, while phthalate monoesters were the most prominent metabolites. The mass loads of most compounds were quite similar across cities, but geographic differences were observed for some biomarkers, such as metabolites of phthalates and alternative plasticizers. Exposure was then assessed for seven substances for which quantitative urinary excretion data are known. Our results indicate that safe reference values were exceeded for several contaminants, including butylated phthalates, bisphenol A, and tris(2-butoxyethyl) phosphate, particularly for toddlers. With this relatively simple method, which requires less sample manipulation, it is possible to promptly identify and monitor exposure to harmful chemicals at the population level using the WBE approach.

Environmental risk assessment of polycarboxylate polymers used in cleaning products in the United States.

Polycarboxylate polymers have been common components of consumer and institutional cleaning products for decades. With interest heightened in the potential environmental impact of polymers, the American Cleaning Institute, the industry trade association of the cleaning products industry in the United States, is reassessing the state of the science regarding the environmental safety of polymers in cleaning products. In this case study, acrylic acid homopolymers and acrylic acid-maleic acid copolymers are evaluated using historical ecotoxicity data that have been reported over the past three decades. The evaluation includes an environmental exposure assessment that is based on recent information regarding the occurrence of those ingredients in cleaning products and market sales data for cleaning products sold in the United States. The ecotoxicity of polycarboxylate polymers is generally low. Consequently, the potential environmental risks associated with their use in cleaning products in the United States are low even when applying very conservative assumptions to the environmental exposure assessment. In addition, there are recent supporting conclusions from assessments by the governments of Australia and Canada that polycarboxylate polymers are polymers of low concern, and the U.S. Environmental Protection Agency has included a number of polycarboxylate polymers among the ingredients on its Safer Chemical Ingredients List based on their low hazard profile.

Combined Assessment of Preschool Childrens' Exposure to Substances in Household Products.

Understanding how indoor-air contaminants affect human health is of critical importance in our developed society. We assessed the combined exposure by inhalation of preschool children and children to household products. A total of 1175 families with 72 infants, 158 toddlers, 230 children, and 239 youths were surveyed to determine the combined respiratory exposure concentrations and amounts associated with 21 substances in eight household product groups. We determined the mean concentrations of these substances in each product, and derived reference toxicity values based on the information gathered in order to identify respiratory health risks. On average, cleaners were used at a rate of 1.0 × 10³ g/month, while coating agents and other substances were used at 43 g/month. The combined inhalation exposure concentrations of methanol to infants and toddlers were 5.1 and 4.2 mg/m³ per month, respectively, with values of 2.1 and 1.7 mg/m³ for isopropanol, respectively. Risks to preschool children and children should be assessed on the basis of the toxicity values of combined exposed hazardous substances, as well as their combined concentrations and amounts. This exposure assessment approach can be used to establish improved guidelines for products that may pose inhalation hazards to preschool children and children.

Polymers Used in US Household Cleaning Products: Assessment of Data Availability for Ecological Risk Assessment.

The purpose of this study was to identify, characterize, and assess data needs for ecological risk of household cleaning product polymers currently being used in the United States (US). Because of their range in properties and functions, polymers are used in a wide variety of household cleaning products, including fabric, dish, and hard surface cleaners. Understanding their potential environmental impact is essential for good ingredient and product stewardship. The household cleaning product polymers were first identified using several databases. Of the 185 polymers initially identified, 120 were eliminated from the list because they did not fit the definition of a polymer, were not well defined (e.g., no Chemical Abstracts Service [CAS] or trade name only), or were not in current use. Forty-seven of the remaining polymers had either adequate environmental fate and hazard data and/or sufficient data for conducting a comprehensive ecological risk assessment and were determined to be of low concern by either the United States Environmental Protection Agency (USEPA), the European Chemicals Agency (ECHA), and/or the Human and Environmental Risk Assessment (HERA) Project. The remaining 18 polymers were determined to need further review because of a lack of publicly available information for conducting ecological risk assessments. Additional data for these 18 polymers could be obtained by accessing privately held data, conducting laboratory tests on their fate and effects in aquatic environments, or by conducting read-across of similar structured polymers. These steps can be utilized by industry to determine where best to dedicate future environmental stewardship efforts. Integr Environ Assess Manag 2019;15:621-632. © 2019 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Evaluating the consumption of chemical products and articles as proxies for diffuse emissions to the environment.

In this study we have evaluated the use of consumption of manufactured products (chemical products and articles) in the EU as proxies for diffuse emissions of chemicals to the environment. The content of chemical products is relatively well known. However, the content of articles (products defined by their shape rather than their composition) is less known and currently has to be estimated from chemicals that are known to occur in a small set of materials, such as plastics, that are part of the articles. Using trade and production data from Eurostat in combination with product composition data from a database on chemical content in materials (the Commodity Guide), we were able to calculate trends in the apparent consumption and in-use stocks for 768 chemicals in the EU for the period 2003-2016. The results showed that changes in the apparent consumption of these chemicals over time are smaller than in the consumption of corresponding products in which the chemicals are present. In general, our results suggest that little change in chemical consumption has occurred over the timespan studied, partly due to the financial crisis in 2008 which led to a sudden drop in the consumption, and partly due to the fact that each of the chemicals studied is present in a wide variety of products. Estimated in-use stocks of chemicals show an increasing trend over time, indicating that the mass of chemicals in articles in the EU, that could potentially be released to the environment, is increasing. The quantitative results from this study are associated with large uncertainties due to limitations of the available data. These limitations are highlighted in this study and further underline the current lack of transparency on chemicals in articles. Recommendations on how to address these limitations are also discussed.

Assessment of androgen receptor agonistic/antagonistic effects on 25 chemicals in household applicants by OECD in vitro stably transfected transcriptional activation assays.

The aim of this study is to assess the androgen receptor (AR) agonistic/antagonistic effects on various chemicals, which are used in household products including cleaning agents and wetted tissues by in vitro OECD test guideline No. 458 (using AR-EcoScreen™ cell line) and the me-too test method (using 22Rv1cell line), which was adopted as OECD project No. 4.99. All chemicals were not determined as AR agonists. However α-dodecyl-ω-hydroxypoly (oxyethylene) and 3-iodo-2-propynyl butylcarbamate have shown a weak AR antagonistic effects with IC50 values of 2.18 ±â€¯0.12 and 4.26 ±â€¯0.17 µg/ml via binding affinity to AR in only 22Rv1/mouse mammary tumor virus using AR transcriptional activation assay, because of their different cytotoxicity on each applied cell line. This report firstly provides information about agonistic/antagonistic effects against human AR of various chemicals including surfactants and biocides by OECD in vitro stably transfected transcriptional activation assays. However, further in vivo and human model studies are needed to confirm their adverse effects.

Pharmacopollution and Household Waste Medicine (HWM): how reverse logistics is environmentally important to Brazil.

Pharmacopollution is a public health and environmental outcome of some active pharmaceutical ingredients (API) and endocrine-disrupting compounds (EDC) dispersed through water and/or soil. Its most important sources are the pharmaceutical industry, healthcare facilities (e.g., hospitals), livestock, aquaculture, and households (patients' excretion and littering). The last source is the focus of this article. Research questions are "What is the Household Waste Medicine (HWM) phenomenon?", "How HWM and pharmacopollution are related?", and "Why is a reverse logistic system necessary for HWM in Brazil?" This article followed the seven steps proposed by Rother (2007) for a systematic review based on the Cochrane Handbook and the National Health Service (NHS) Center for Reviews Dissemination (CDR) Report. The HWM phenomenon brings many environmental, public health, and, social challenges. The insufficient data is a real challenge to assessing potential human health risks and API concentrations. Therefore, the hazard of long-term exposure to low concentrations of pharmacopollutants and the combined effects of API mixtures is still uncertain. HWM are strongly related to pharmacopollution, as this review shows. The Brazilian HWM case is remarkable because it is the fourth pharmaceutical market (US$ 65,971 billion), with a wide number of private pharmacies and drugstores (3.3: 10,000 pharmacy/inhabitants), self-medication habits, and no national take-back program. The HWM generation is estimated in 56.6 g/per capita, or 10,800 t/year. The absence of a reverse logistics for HWM can lead to serious environmental and public health challenges. The sector agreement for HWM is currently under public consultation.

Probabilistic derivation of the interspecies assessment factor for skin sensitization.

An interspecies sensitization assessment factor (SAF) is used in the quantitative risk assessment (QRA) for skin sensitization when a murine-based NESIL (No Expected Sensitization Induction Level) is taken as point of departure. Several studies showed that, on average, the murine sensitization threshold is in good correspondence with that determined in humans. However, on an individual level, the murine and human sensitization thresholds may differ considerably. In this study, the interspecies SAF was quantified by using a probabilistic approach, to be able to take these cases into account. As expected, the geometric means of the probability distributions of murine and human sensitization threshold ratios were close to one, but taking the 95 th percentile of these distributions resulted in an interspecies SAF of 15. By using this value, one is sure that with 95% probability, the sensitization threshold determined in mice does not underestimate the human threshold. It can be concluded that a murine-based NESIL requires the use of an interspecies SAF (of 15) in the QRA for skin sensitization, to correct for the differences between mice and humans. This empirically derived interspecies SAF contributes to refinement of the risk assessment methodology.

Toward refined environmental scenarios for ecological risk assessment of down-the-drain chemicals in freshwater environments.

Current regulatory practice for chemical risk assessment suffers from the lack of realism in conventional frameworks. Despite significant advances in exposure and ecological effect modeling, the implementation of novel approaches as high-tier options for prospective regulatory risk assessment remains limited, particularly among general chemicals such as down-the-drain ingredients. While reviewing the current state of the art in environmental exposure and ecological effect modeling, we propose a scenario-based framework that enables a better integration of exposure and effect assessments in a tiered approach. Global- to catchment-scale spatially explicit exposure models can be used to identify areas of higher exposure and to generate ecologically relevant exposure information for input into effect models. Numerous examples of mechanistic ecological effect models demonstrate that it is technically feasible to extrapolate from individual-level effects to effects at higher levels of biological organization and from laboratory to environmental conditions. However, the data required to parameterize effect models that can embrace the complexity of ecosystems are large and require a targeted approach. Experimental efforts should, therefore, focus on vulnerable species and/or traits and ecological conditions of relevance. We outline key research needs to address the challenges that currently hinder the practical application of advanced model-based approaches to risk assessment of down-the-drain chemicals. Integr Environ Assess Manag 2017;13:233-248. © 2016 SETAC.

An effective dose assessment technique with NORM added consumer products using skin-point source on computational human phantom.

The aim of this study is to develop the assessment technique of the effective dose by calculating the organ equivalent dose with a Monte Carlo (MC) simulation and a computational human phantom for the naturally occurring radioactive material (NORM) added consumer products. In this study, we suggests the method determining the MC source term based on the skin-point source enabling the convenient and conservative modeling of the various type of the products. To validate the skin-point source method, the organ equivalent doses were compared with that by the product modeling source of the realistic shape for the pillow, waist supporter, sleeping mattress etc. Our results show that according to the source location, the organ equivalent doses were observed as the similar tendency for both source determining methods, however, it was observed that the annual effective dose with the skin-point source was conservative than that with the modeling source with the maximum 3.3 times higher dose. With the assumption of the gamma energy of 1MeV and product activity of 1Bqg-1, the annual effective doses of the pillow, waist supporter and sleeping mattress with skin-point source was 3.09E-16SvBq-1year-1, 1.45E-15SvBq-1year-1, and 2,82E-16SvBq-1year-1, respectively, while the product modeling source showed 9.22E-17SvBq-1year-1, 9.29E-16SvBq-1year-1, and 8.83E-17SvBq-1year-1, respectively. In conclusion, it was demonstrated in this study that the skin-point source method could be employed to efficiently evaluate the annual effective dose due to the usage of the NORM added consumer products.

American Contact Dermatitis Society Contact Allergy Management Program: An Epidemiologic Tool to Quantify Ingredient Usage.

BACKGROUND: The usage prevalence of ingredients in topical products is important to dermatologists and industry. OBJECTIVE: To determine the prevalence of methylisothiazolinone (MI) in various types of consumer products METHODS: The Contact Allergy Management Program (CAMP) database was mapped and sorted in spreadsheet format to determine the prevalence of MI in various types of consumer products. RESULTS: Methylisothiazolinone was found in 13.2% of 4660 total products in CAMP. High usage of MI was seen in dishwashing products (64%), shampoos (53%), bathroom/kitchen/all-purpose cleaners (47%), hair conditioners (45%), hair dyes (43%), laundry additives/fresheners/softeners (30%), soaps/cleansers (29%), and surface cleaners/disinfectants (27%). Of the products containing MI, MI alone (without methylchloroisothiazolinone) was most common in makeup products (100%), cleaning/dish/laundry products (>99%), moisturizers (82%), shaving products (78%), sunscreens (71%), and antiaging products (67%). CONCLUSIONS: The American Contact Dermatitis Society's CAMP is a valuable tool to collect epidemiologic data on the incidence of specific ingredient usage in various types of topical products.

Effective dose evaluation of NORM-added consumer products using Monte Carlo simulations and the ICRP computational human phantoms.

The aim of this study is to evaluate the potential hazard of naturally occurring radioactive material (NORM) added consumer products. Using the Monte Carlo method, the radioactive products were simulated with ICRP reference phantom and the organ doses were calculated with the usage scenario. Finally, the annual effective doses were evaluated as lower than the public dose limit of 1mSv y(-1) for 44 products. It was demonstrated that NORM-added consumer products could be quantitatively assessed for the safety regulation.

Risk assessment of down-the-drain chemicals at large spatial scales: Model development and application to contaminants originating from urban areas in the Saint Lawrence River Basin.

Chemicals released into freshwater systems threaten ecological functioning and may put aquatic life and the health of humans at risk. We developed a new contaminant fate model (CFM) that follows simple, well-established methodologies and is unique in its cross-border, seamless hydrological and geospatial framework, including lake routing, a critical component in northern environments. We validated the model using the pharmaceutical Carbamazepine and predicted eco-toxicological risk for 15 pharmaceuticals in the Saint-Lawrence River Basin, Canada. The results indicated negligible to low environmental risk for the majority of tested chemicals, while two pharmaceuticals showed elevated risk in up to 13% of rivers affected by municipal effluents. As an integrated model, our CFM is designed for application at very large scales with the primary goal of detecting high risk zones. In regulatory frameworks, it can help screen existing or new chemicals entering the market regarding their potential impact on human and environmental health. Due to its high geospatial resolution, our CFM can also facilitate the prioritization of actions, such as identifying regions where reducing contamination sources or upgrading treatment plants is most pertinent to achieve targeted pollutant removal or to protect drinking water resources.

The fate of two isothiazolinone biocides, 5-chloro-2-methylisothiazol-3(2H)-one (CMI) and 2-methylisothiazol-3(2H)-one (MI), in liquid air fresheners and assessment of inhalation exposure.

There exist public concerns regarding the two most widely used isothiazolinones (5-chloro-2-methylisothiazol-3(2H)-one (CMI) and 2-methylisothiazol-3(2H)-one (MI)) in various consumer products because they cause allergic responses in dermatitis and are potentially harmful when inhaled. Hydrolysis and photolysis tests for CMI and MI at pH 4, 7, and 9 were performed to evaluate their stability. While MI did not degrade under the test conditions, CMI slightly degraded at pH 9 via hydrolysis and at pH 4 via photolysis. To better understand human exposure to MI and CMI during the use of consumer products, the vaporization rates of MI and CMI from two commercial air fresheners were quantified in a custom-made chamber. The evaporation of MI was almost negligible over 7 d, whereas a significant amount of CMI evaporated over the same period. Because the volume of air freshener decreases over time due to evaporation of water, the MI concentration in the product increased by a factor of 1.8-2.2. The air concentration of CMI was predicted using a ConsExpo model using a fixed weight fraction (model 1) and a new model that reflects changes in the concentrations of active ingredients and the product volume over time (model 2). The concentration determined using model 1 reached a steady-state value of 0.032 µg L(-1), whereas that predicted using model 2 increased consistently. Inhalation exposure was also assessed using two exposure scenarios: a room and a car. Both calculated values of margin of exposure were much higher than 300, indicating a negligible inhalation risk.

A pilot study on the assessment of trace organic contaminants including pharmaceuticals and personal care products from on-site wastewater treatment systems along Skaneateles Lake in New York State, USA.

On-site wastewater treatment systems (OWTSs or septic systems) are designed to treat and dispose effluents on the same property that produces the wastewater. Approximately 25% of the U.S. population is served by such facilities. Nevertheless, studies on the treatment efficiency and discharge of organic contaminants through septic effluents are lacking. This pilot study showed the occurrence of organic contaminants including pharmaceuticals and personal care products (PPCPs), perfluoroalkyl surfactants (PFASs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs) in septic effluents, adjacent lake water samples, household drinking water in homes that use lake water or a well adjacent to the lake as a source of drinking water, and offshore lake water samples. Septic effluent as well as lake and tap water samples were collected from several households with OWTSs around Skaneateles Lake located in central New York. The advanced on-site systems were installed in some households for the purpose of limiting nutrient levels in the effluent to protect the local surface water. Additionally, because many of these systems serve homes with limited land, advanced treatment systems were needed. The median concentrations of ten PPCPs (ranged from 0.45 to 388 ng/L) and eleven PFASs (ranged from 0.20 to 14.6 ng/L) in septic water were significantly higher (p ≤ 0.01) than in lake water samples. The median concentrations of PPCPs and PFASs in lake and tap water samples were not significantly different (p ≥ 0.65). The median concentrations of ∑PBDEs in septic, lake, and tap water samples were 7.47, 3.49, and 2.22 ng/L, respectively, and those for ∑PCBs were 33.1, 29.2, and 28.6 ng/L, respectively. The mass flux of PPCPs (i.e. the mass flow of PPCPs per unit area per unit time) through the disposal of treated septic effluent from textile biofilter and aerobic treatments to the dispersal unit ranged from 12 (carbamazepine) to 66900 µg/m(2)/day (caffeine) whereas that for PFASs ranged from 7.0 (perfluorobutanesulfonate) to 833 µg/m(2)/day (perfluorooctanoic acid). Based on the ratio of measured concentrations and method detection limit, triclocarban, perfluorooctanoic acid, and perfluorooctanesulfonate have the potential to be used as chemical tracers of septic water contamination in Skaneateles Lake. The median concentrations of atenolol, a beta-blocker drug, in septic water were significantly (ρ = 0.86, p = 0.01) correlated with enterococci counts.

Widespread occurrence of benzophenone-type UV light filters in personal care products from China and the United States: an assessment of human exposure.

Benzophenone-3 (BP-3) is a sunscreen agent used in a variety of personal care products (PCPs) for the protection of human skin and hair from damage by ultraviolet (UV) radiation. Concerns have been raised over exposure of humans to BP-3, owing to the estrogenic potential of this compound. Nevertheless, the levels and profiles of BP-3 in PCPs and sources of exposure of humans to this estrogenic compound are not well-known. In this study, concentrations of BP-3 were determined in seven categories of 231 PCPs collected from several cities in China (n = 117) and the United States (U.S.) (n = 114), using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). BP-3 was found in the majority (81%) of the samples analyzed, at concentrations as high as 0.148%. The highest BP-3 concentrations (geometric mean [GM]: 548; median: 530 ng/g) were found in skin lotions (including sunscreen lotions), followed by makeup products (284; 221 ng/g). PCPs collected from the U.S. contained higher concentrations of BP-3 than those collected from China. On the basis of the concentrations measured and daily usage rates of PCPs, we estimated the daily intake of BP-3 through dermal absorption from the use of PCPs. The GM and 95th percentile exposure doses to BP-3 were 0.978 and 25.5 µg/day, respectively, for adult women in China, which were 2 orders of magnitude lower than those found for adult women in the U.S. (24.4 and 5160 µg/day). Skin lotions and face creams contributed to the preponderance of daily BP-3 exposures (>80%).

Does microbicide use in consumer products promote antimicrobial resistance? A critical review and recommendations for a cohesive approach to risk assessment.

The increasing use of microbicides in consumer products is raising concerns related to enhanced microbicide resistance in bacteria and potential cross resistance to antibiotics. The recently published documents on this topic from the European Commission have spawned much interest to better understand the true extent of the putative links for the benefit of the manufacturers, regulators, and consumers alike. This white paper is based on a 2-day workshop (SEAC-Unilever, Bedford, United Kingdom; June 2012) in the fields of microbicide usage and resistance. It identifies gaps in our knowledge and also makes specific recommendations for harmonization of key terms and refinement/standardization of methods for testing microbicide resistance to better assess the impact and possible links with cross resistance to antibiotics. It also calls for a better cohesion in research in this field. Such information is crucial to developing any risk assessment framework on microbicide use notably in consumer products. The article also identifies key research questions where there are inadequate data, which, if addressed, could promote improved knowledge and understanding to assess any related risks for consumer and environmental safety.

Feather meal: a previously unrecognized route for reentry into the food supply of multiple pharmaceuticals and personal care products (PPCPs).

Antimicrobials used in poultry production have the potential to bioaccumulate in poultry feathers but available data are scarce. Following poultry slaughter, feathers are converted by rendering into feather meal and sold as fertilizer and animal feed, thereby providing a potential pathway for reentry of drugs into the human food supply. We analyzed feather meal (n = 12 samples) for 59 pharmaceuticals and personal care products (PPCPs) using EPA method 1694 employing liquid chromatography tandem mass spectrometry (LC/MS/MS). All samples tested positive and six classes of antimicrobials were detected, with a range of two to ten antimicrobials per sample. Caffeine and acetaminophen were detected in 10 of 12 samples. A number of PPCPs were determined to be heat labile during laboratory simulation of the rendering process. Growth of wild-type E. coli in MacConkey agar was inhibited by sterilized feather meal (p = 0.01) and by the antimicrobial enrofloxacin (p < 0.0001) at levels found in feather meal. Growth of a drug-resistant E. coli strain was not inhibited by sterilized feather meal or enrofloxacin. This is the first study to detect antimicrobial residues in feather meal. Initial results suggest that more studies are needed to better understand potential risks posed to consumers by drug residues in feather meal.

Characterization of post-consumer polyolefin wastes by hyperspectral imaging for quality control in recycling processes.

In this paper new analytical inspection strategies, based on hyperspectral imaging (HSI) in the VIS-NIR and NIR wavelength ranges (400-1000 and 1000-1700 nm, respectively), have been investigated and set up in order to define quality control logics that could be applied at industrial plant level for polyolefins recycling. The research was developed inside the European FP7 Project W2Plastics "Magnetic Sorting and Ultrasound Sensor Technologies for Production of High Purity Secondary Polyolefins from Waste". The main aim of the project is the separation of pure polyethylene and polypropylene adopting an innovative process, the magnetic density separation (MDS). Spectra of plastic particles and contaminants resulting from post-consumer complex wastes and of virgin polyolefins have been acquired by HSI and by Raman spectroscopy. The classification results obtained applying principal component analysis (PCA) on HSI data have been compared with those obtained by Raman spectroscopy, in order to validate the proposed innovative methodology. Results showed that HSI sensing techniques allow to identify both polyolefins and contaminants. Results also demonstrated that HSI has a great potentiality as a tool for quality control of feed (identification of contaminants in the plastic waste) and of the two different pure polypropylene and polyethylene flow streams resulting from the MDS-based recycling process.

Assessment of sensitization risk of a laundry pre-spotter containing protease.

When proteolytic enzymes were first introduced to common laundry detergents in the 1960s, their ability to cause hypersensitivity due to exposure by inhalation was soon recognized as a problem, especially for production workers. Subsequently, formulations and manufacturing methods were developed to minimize exposure to enzymes via inhaled dust particles. Although detergents containing proteases are now considered safe for consumers, the experience with laundry pre-spotter products is not as extensive. Two studies were undertaken to examine the risk of sensitization to protease (i.e. Savinase(®)) used in a trigger-spray laundry pre-spotter product. The first was a laboratory study simulating a very heavy-use scenario in a controlled environment cubical chamber (14.5 m(3)). The product was applied to a series of fabric targets held vertically over a standard washing machine. Eight replicates of the experiment were done, using 30 sprays for each replicate. Airborne particle distributions in the breathing zone were characterized using a TSI particle analyzer. Enzyme concentrations in air were measured using PTFE membrane filters that were frozen until analyzed by an enzyme linked immunosorbent assay (ELISA). Results indicated that aerosol concentrations returned to baseline within 10 min, during which the average enzyme concentration in air was 17 ± 1.6 and 12 ± 0.92 ng/m(3) using low- and high-volume samplers, respectively. The corresponding amount of enzyme that could be inhaled was significantly less than allowed in occupational situations. The second study was a 6-month, controlled-use study involving approximately 100 subjects with confirmed atopic status by skin prick testing with common aeroallergens. The study involved daily exaggerated use of the pre-spotter product for 6 months, with prick testing for the protease carried out at baseline, 3 and 6 months. Results from the clinical study indicated that none of the subjects exhibited reactions that would indicate sensitization to the protease by inhalation. The principal limitations of the study were the relatively small number of subjects and the limited duration (96 completed the entire 6-month exposure program).