Bis 2-ethylhexyl Adipate Research Articles

Quantification of overall migration levels from poly (vinyl chloride) films: Effects of gamma and electron beam radiation

This study investigated the overall migration from Poly (vinyl chloride) (PVC) polymer films into food simulants, after gamma irradiation ( 60 Co) or electron beam radiation. PVC polymer films containing di-(2-ethylhexyl) adipate (DEHA) and epoxidized soybean oil were stored under controlled temperature (24 ± 1 o C) and moisture (50 ± 5 %) for 2 days. These films were supported on a stainless-steel plates and specimens were subjected to ionizing radiation treatment with gamma radiation from a 60 Co source (dose rate = 20 Gy/min) or electron beam radiation (dose rate = 120 Gy/min) at absorbed doses equal to 0, 10, 25 and 50 kGy. Overall packing migrants were evaluated on different food simulants (distilled water, 3 % w/v acetic acid and 10 % v/v ethanol) as a function of time (24, 48 and 72 hours). Results of overall migration levels showed that the treatment with radiation doses above 10 kGy promoted a significant increase of the overall packing migrants levels into all aqueous food simulants (p < 0.05). Overall migration levels were also enhanced with increasing exposure time to food simulants.

Carbon nanotube composite microspheres as a highly efficient solid-phase microextraction coating for sensitive determination of phthalate acid esters in water samples

Multiwalled carbon nanotubes (MWCNTs) on polystyrene (PS) microspheres have been designed and prepared by layer-by-layer assembly via electrostatic interaction. MWCNTs@PS was characterized by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The new materials were employed as a novel solid-phase microextraction (SPME) coating to enrich trace level of phthalate acid esters (PAEs) in water samples. Five PAEs, di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-2-ethylhexyl adipate (DEHA), di-2-ethylhexyl phthalate (DEHP) and di-n-octyl phthalate (DOP), were studied in this work. The Box-Behnken design was applied to calculate optimum extraction factors affecting the extraction efficiency using a response surface. In the optimized conditions, the developed technique achieved high enrichment factors (738–2347), low limits of detection (0.0012–0.018μgL−1) and wide linearity (0.001–5μgL−1) for detecting PAEs. The method was successfully applied to analyze PAEs in real environmental water samples with recovery ranging from 73.4% to 103.8%. The results demonstrated that MWCNTs@PS are a promising coating material in the SPME of PAEs at trace levels from environmental samples.

Simultaneous GC-MS determination of seven phthalates in total and migrated portions of paper cups.

Phthalate acid esters are widely used as plasticizers to impart plastic flexibility in various industrial applications. In this study, the content of seven phthalates, dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), di-(2-ethylhexyl) adipate (DEHA), di-2-ethylhexyl phthalate (DEHP), di-n-octyl phthalate (DNOP), di-isononyl phthalate (DINP), and di-isodecyl phthalate (DIDP) were determined in paper cups using gas chromatography-mass spectrometry (GC-MS). In addition, the potential migration of these seven phthalates from paper cups into various food stimulants under different conditions was evaluated. The levels of DBP, DEHA, DEHP, and DNOP were in the ranges of 0.07-3.14, 0.16-42.69, 0.45-58.56, and 0.3-2.4mg/kg, respectively. Meanwhile, BBP, DINP, and DIDP were not detected in most of the tested samples. In the migration test, DEHA was released to 50% ethanol and n-heptane in a time-dependent manner and the maximum migration levels were 65.62 ± 3.61 and 95.56 ± 19.76μg/L, respectively. The release of other phthalates was very low or negligible. These results demonstrated that paper cups are not a significant source of phthalate exposure; however, DEHA could be released from paper cups into alcoholic beverages or oily liquid beverages in the human diet.

Di-(2-ethylhexyl) adipate and 20 phthalates in composite food samples from the 2013 Canadian Total Diet Study

A sensitive and selective GC-MS method was developed and used for simultaneous analysis of di-(2-ethylhexyl) adipate (DEHA) and 20 selected phthalates in the food samples from the 2013 Canadian Total Diet Study. At least one of the 21 target chemicals was detected in 141 of the 159 different food composite samples analysed. However, only seven of the 21 target chemicals were detected, with di-(2-ethylhexyl) phthalate (DEHP) and DEHA being detected most frequently, in 111 and 91 different food composite samples, respectively, followed by di-n-butyl phthalate (DBP) (n = 44), n-butyl benzyl phthalate (BBzP) (32), di-iso-butyl phthalate (DiBP) (27), di-ethyl phthalate (DEP) (3), and di-cyclohexyl phthalate (DCHP) (1). Levels of DEP (di-ethyl phthalate), DiBP, DBP, BBzP and DCHP were low, in general, with average concentrations of 9.63, 8.26, 23.2, 12.4 and 64.9 ng g–1, respectively. Levels of DEHA and DEHP varied widely, ranging from 1.4 to 6010 ng g–1 and from 14.4 to 714 ng g–1, respectively. High levels of DEHA were found mainly in the composite samples where the individual food items used to prepare the composite were likely packaged in polyvinyl chloride (PVC) wrapping film, while the highest DEHP levels were found in the vegetable and fruit samples.

Non-phthalate plasticizers in German daycare centers and human biomonitoring of DINCH metabolites in children attending the centers (LUPE 3).

Plasticizers have been widely used for decades as additives in diverse applications, including consumer and building products, toys, cables, and floorings. Due to toxicological concerns and restrictions of different dialkyl ortho-phthalates, other plasticizers have been increasingly used in recent years. Therefore, di-isononyl cyclohexane-1,2-dicarboxylate (DINCH), di(2-ethylhexyl) terephthalate (DEHT), di(2-ethylhexyl) adipate (DEHA), acetyl tri-n-butyl citrate (ATBC), and trioctyl trimellitate (TOTM) plasticizer levels in indoor air and dust samples from 63 daycare centers in Germany were measured. Moreover, the urine samples of 208 children who attend 27 of these facilities were analyzed for the presence of four DINCH metabolites. DINCH, DEHT, and DEHA were present in indoor air with median values of 108 ng/m(3), 20 ng/m(3), and 34 ng/m(3), respectively. Median values of 302 mg/kg for DINCH, 49 mg/kg for DEHA, 40 mg/kg for DEHT, and 24 mg/kg ATBC were found in dust. In the urine samples, the three secondary metabolites of DINCH were observed with median values (95th percentiles) of 1.7 μg/l (10.0 μg/l) for OH-MINCH, 1.5 μg/l (8.0 μg/l) for oxo-MINCH, and 1.1 μg/l (6.1 μg/l) for cx-MINCH. Overall, these metabolite levels are orders of magnitude lower than the current HBM I values set by the German Human Biomonitoring Commission. Using general exposure assumptions, the intake resulting from dust ingestion and inhalation is low for children. The total daily DINCH intake calculated from biomonitoring data was 0.5 μg/kg b.w. using median values and 9.8 μg/kg b.w. as the maximum value. At present, non-phthalate plasticizers, especially DINCH, can be found in considerable amounts in dust samples from daycare centers and as DINCH metabolites in the urine of children. In relation to previous studies, the concentrations of DINCH in dust and urine have an increasing time trend. Compared with tolerable daily intake values, the total daily intake of DINCH reached only 1% of its maximum value to date; however, due to its increased use, higher exposure of DINCH is expected in the future.

Migration of monomers and plasticizers from packed foods and heated microwave foods using QuEChERS sample preparation and gas chromatography/mass spectrometry

The objective of this study was to evaluate the migration of monomers and plastic additives in microwave heated homemade courses and in packed liquid food. Compounds studied were 3 phthalates, 4-tert-octylphenol (OP), 4-nonylphenol (NP), bisphenol A (BPA) and di(2-ethylhexyl)adipate (DEHA). A QuEChERS based method was optimized for the analysis of these compounds in solid or liquid packed and retailed food. Using gas chromatography coupled to mass spectrometry, recoveries ranged from 49 ± 16% (OP) to 130 ± 16% (BPA) and from 63 ± 22% (OP) to 127 ± 29% (NP) in solid and liquid foods, with limits of detection below 14.37 ng g−1 and 2.25 ng mL−1, respectively. NP showed the highest mean level in homemade foods (1064 ± 363 ng g−1 wet weight) and reheating did not produce an increase in the levels detected. Phthalates and DEHA were detected at low concentrations. Among liquid foods, meat broth mean concentrations of NP were of 9.61 ± 1.93 ng mL−1 and of 9.68 ± 1.75 ng mL−1 for butylbenzylphthalate in fish broth, while in wine, the most abundant compound was di-n-butylphthalate. Overall, the developed QuEChERS method permitted to determine the presence of investigated chemicals in packed food allowing the evaluation of compounds that can affect food quality.

Migration of di‐(2‐ethylhexyl)adipate (DEHA) and acetyl tributyl citrate (ATBC) plasticizers from PVC film into the food stimulant of isooctane

Chemical migration from food packing is influenced by several factors such as nature of chemicals, complexity of food, temperature, packing material used and properties of the migrating substances. Chemical compounds that are incorporated within polymeric packaging materials may interact with food components during processing or storage and migrate into the food by jeopardizing the food safety. This migration is higher if food remains in contact with packing material for extended time. Polyvinyl chloride (PVC) film such as di‐(2‐ethylhexyl) adipate (DEHA) and acetyl tributyl citrate (ATBC) are still widely used as a food packing material due to its flexibility, transparency and low water permeability. The present study covers the main migration phenomena of both plasticizers (di‐(2‐ethylhexyl) adipate (DEHA) and acetyl tributyl citrate (ATBC)) from PVC‐film into isooctane food stimulant using a direct gas chromatographic method. An exposure period of 48 h at 30 °C and 4 °C was used. The obtained results showed DEHA levels ranging of 7.2 mg/dm2 while, no ATBC migration from PVC‐film was observed. Results are discussed in relation to EU legislation proposed upper limit for DEHA specific migration (18 mg/L or 3 mg/dm2) and overall migration limit (OM) of 10 mg/dm2.

Controle Sanitário de Filmes Flexíveis de PVC Comercializados no Estado do Rio de Janeiro

n total, 37 samples of flexible PVC films were analyzed for specific migration of di-(2-ethylhexyl) phthalate (DEHP) and di-(2-ethylhexyl) adipate (DEHA) from packaging to fatty foods, using simulant. The Resolution n. 17, of March 17, 2008, published by ANVISA, establishes specific migration limits for DEHP in 1.5 mg kg−1 of simulant and for DEHA in 18 mg kg−1 of simulant. The migration test was performed through contact between a 1-dm2 PVC film cutout and 100 mL of food simulant, ethanol 95% (v/v), for 48 h at 20oC. The migrations of DEHP and DEHA were determined by gas chromatography with a flame ionization detector and a fused silica column internally coated with a stationary phase consisting of 5% phenylmethylsilicone. The results from the samples showed specific migration of DEHP ranging between not detectable (< 0.35 mg kg−1) and 304 mg kg−1 of food simulant and between not detectable (< 2.23 mg kg−1) and 231 mg kg−1 of food simulant for DEHA. Among the tested samples, 95% had results above the limit established by legislation.

Occurrence of Di-(2-Ethylhexyl) Adipate and Phthalate Plasticizers in Samples of Meat, Fish, and Cheese and Their Packaging Films

Di-(2-ethylhexyl) adipate (DEHA) and phthalates are commonly used as plasticizers to soften polyvinyl chloride products. Because both DEHA and certain phthalates have been identified as priority chemicals for assessment of human health risk under the Government of Canada's Chemicals Management Plan, a comprehensive targeted survey was conducted to investigate the occurrence of DEHA and eight phthalates (di-methyl phthalate, di-ethyl phthalate, di-n-butyl phthalate, di-iso-butyl phthalate, butyl benzyl phthalate, di-n-hexyl phthalate, d-(2-ethylhexyl) phthalate, and di-n-octyl phthalate) in a total of 118 samples of meat (beef, pork, and chicken), fish, and cheese packaged mostly in cling films. The eight phthalates were not detected in any of the food packaging, but DEHA was detected in most of the cling films, indicating that although DEHA-plasticized films (e.g., polyvinyl chloride film) are currently being used by most grocery stores, nonplasticized cling films such as polyethylene film, are also being used by some stores. DEHA was not detected in any of the 10 cheese samples packaged in nonplasticized rigid plastics but was detected in all 30 cheese samples packaged in DEHA-plasticized cling films at levels from 0.71 to 879 μg/g, with an average of 203 μg/g. Only DEHA was detected in the beef, pork, chicken, and fish samples packaged in DEHA-plasticized cling films but at considerably lower levels than those found in cheese, with averages of 6.3, 9.1, 2.5, and 5.9 μg/g, respectively. Among the eight phthalates, only di-(2-ethylhexyl) phthalate (DEHP) was detected in a few cheese samples at levels from 0.29 to 15 μg/g, with an average of 2.8 μg/g; these levels were very likely due to environmental contamination. Levels of DEHA found in most of the cheese samples from this study are above the European specific migration limit of 18 mg/kg for DEHA in food or food simulants, and levels of phthalates (i.e., DEHP) were low.

고농축 복합화약 시뮬란트의 유변학적 특성: 벽면 미끄러짐, 틱소트로피, 유동불안정성

고분자 결합제로 hydroxyl terminated polybutadiene(HTPB)와 폴리에틸렌 플라스토머인 Exact를 사용한 고농축 복합화약 시뮬란트의 유변학적 특성을 연구하였다. 충전제로서 설탕 및 research department explosive(RDX)와 물리적 특성이 유사한 Dechlorane을 사용하였다. HTPB 사용시에는 가소제로 diethyl hexyl adipate(DEHA or DOA)를 첨가하기도 하였다. 농축 현탁계의 혼화는 시그마 블레이드가 장착된 회분식 혼련기(Rheomix 600, Haake) 를 사용하였고 유변학적 물성은 평판-평판 레오미터 및 모세관 레오미터를 이용하였다. 고농축 결합제/충전제 현탁계의 벽면 미끄러짐 현상, 전단 히스테리시스에 따른 틱소트로피 거동, 전단속도 및 충전제 첨가에 따른 유동불안정성 변화를 조사하였다. The rheological characteristics of highly concentrated polymer bonded explosive simulant were studied. Hydroxyl terminated polybutadiene (HTPB) and polyethylene plastomer (Exact) were used as binders. Sugar and Dechlorane particles whose physical properties are similar to research department explosive (RDX) were used as fillers. When HTPB was used, diethyl hexyl adipate (DEHA or DOA) was used as a plasticizer together for some cases. Highly concentrated suspensions were mixed in a batch melt mixer (Rheomixer 600, Haake) and rheological properties were measured by plate-plate and capillary rheometers. Wall slip phenomena, thixotropy with shear hysteresis, and flow instability were investigated as shear rate and amount of fillers changed.

Simultaneous analysis of phthalates, adipate and polycyclic aromatic hydrocarbons in edible oils using isotope dilution-gas chromatography–mass spectrometry

A method for simultaneous determination of 12 priority phthalates, adipate and polycyclic aromatic hydrocarbons (PAHs) in edible oils by isotope dilution-gas chromatography–mass spectrometry (ID-GC–MS) was developed for fast, accurate and trace analysis. The extraction and clean-up procedures were optimised, and using stable isotope-labelled internal standards for each analyte, relative standard deviations (RSDs) of 0.92–10.6% and spiked sample recoveries of 80.6–97.8% were obtained. Limits of detection for PAHs were in the range of 0.15–0.77 µg/kg and those for phthalates were in the range of 4.6–10.0 µg/kg. The calibration curves exhibited good linearities with regression coefficients of R2 ≥ 0.99. Twelve edible oils were examined to evaluate the efficiency of this method. Among the 12 analytes, dibutyl phthalates (DBP), diethylhexyl phthalates (DEHP), diethylhexyl adipate (DEHA), benzo[a]anthracene (B[a]A), chrysene (Chry) and benzo[b]fluoranthene (B[b]F) were detected in the range of 1.17–806 µg/kg.

Effect of bottling and storage on the migration of plastic constituents in Spanish bottled waters

Bottled water is packaged in either glass or, to a large extent, in plastic bottles with metallic or plastic caps of different material, shape and colour. Plastic materials are made of one or more monomers and several additives that can eventually migrate into water, either during bottle manufacturing, water filling or storage. The main objective of the present study was to carry out a comprehensive assessment of the quality of the Spanish bottled water market in terms of (i) migration of plastic components or additives during bottling and during storage and (ii) evaluation of the effect of the packaging material and bottle format on the migration potential. The compounds investigated were 5 phthalates, diethylhexyl adipate, alkylphenols and bisphenol A. A set of 362 bottled water samples corresponding to 131 natural mineral waters and spring waters sources and 3 treated waters of several commercial brands were analysed immediately after bottling and after one-year storage (a total of 724 samples). Target compounds were detected in 5.6% of the data values, with diethyl hexyl phthalate and bisphenol A being the most ubiquitous compounds detected. The total daily intake was estimated and a comparison with reference values was indicated.

Diverse Influences of Androgen-Disrupting Chemicals on Immune Responses Mounted by Macrophages

Androgen-disrupting chemicals (ADCs) can alter male sexual development. Although the effects of ADCs on hormone disruption have been studied, their influence on the immune response is not fully understood. To investigate the effects of ADCs on innate immunity, we tested eight candidate ADCs for their influence on macrophages by measuring nitric oxide (NO) production and cell viability. Our results showed that treatment with a mixture of lipopolysaccharide and hexachlorobenzene increased NO production in RAW 264.7 cells, a murine macrophage cell line. In contrast, compared to exposure to a negative control, exposure to di-2-ethylhexyl adipate (DEHA), benzylbutyl phthalate (BBP), testosterone (TTT), or permethrin decreased NO production. DEHA, BBP, and TTT inhibited NO production in an inducible nitric oxide synthase-dependent manner. Treatment with bisphenol A (BPA), nonylphenol (NNP), or tributyltin chloride (TBTC) reduced NO production and induced cell death. While BPA induced RAW 264.7 cell death through apoptosis, NNP and TBTC caused cell death through necrosis. These results offer insights into the influences of ADCs on the innate immune system.

Di-(2-Ethylhexyl) Adipate in Selected Total Diet Food Composite Samples

Polyvinyl chloride (PVC) food-wrapping films plasticized with di-(2-ethylhexyl) adipate (DEHA) are commonly used by grocery stores in Canada to rewrap meat, poultry, fish, cheese, and other foods. DEHA was assessed as part of the Government of Canada's Chemicals Management Plan. The main source of exposure for most age groups was expected to be food. Although the margin of exposure from food and beverages is considered to be adequately protective, the Government of Canada committed to performing targeted surveys of DEHA in foods and food packaging materials to better define Canadian exposure to DEHA through dietary intake. In order to determine whether more-comprehensive targeted surveys on DEHA in foods should be conducted, 26 food composite samples from the 2011 Canadian total diet study were selected and analyzed for DEHA using a method based on solvent and dispersive solid-phase extraction and gas chromatography-mass spectrometry. These 26 food composites include cheese, meat, poultry, fish, and fast foods, and PVC films were likely used in packaging the individual foods used to make the composites. DEHA was detected in most of the meat, poultry, and fish composite samples, with the highest concentration found in ground beef (11 μg/g), followed by beef steak (9.9 μg/g), freshwater fish (7.8 μg/g), poultry liver pâté (7.4 μg/g), fresh pork (6.9 μg/g), cold cuts and luncheon meats (2.8 μg/g), veal cutlets (2.1 μg/g), roast beef (1.3 μg/g), lamb (1.2 μg/g), and organ meats (0.20 μg/g). Targeted surveys should be conducted to investigate the presence of DEHA in various foods packaged with PVC films in more detail and provide updated occurrence data for accurate human exposure assessment.

In Vitro Metabolites of Di-2-ethylhexyl Adipate (DEHA) as Biomarkers of Exposure in Human Biomonitoring Applications

Di-2-ethylhexyl adipate (DEHA) is a common plasticizer used in food packaging. At high doses, DEHA can cause adverse health effects in rats. Although the potential for human exposure to DEHA is high, no DEHA specific biomarkers are identified for human biomonitoring. Using human liver microsomes, we investigated the in vitro phase I metabolism of DEHA and its hydrolytic metabolite mono-2-ethylhexyl adipate (MEHA) and, for comparison purposes, of the analogous di-2-ethylhexyl phthalate (DEHP) and its hydrolytic metabolite mono-2-ethylhexyl phthalate. We unequivocally identified MEHA, a DEHA specific biomarker, and adipic acid, a nonspecific biomarker, using authentic standards. On the basis of their mass spectrometric fragmentation patterns, we tentatively identified two other DEHA specific metabolites: mono-2-ethylhydroxyhexyl adipate (MEHHA) and mono-2-ethyloxohexyl adipate (MEOHA), analogous to the oxidative metabolites of DEHP. Interestingly, although adipic acid was the major in vitro metabolite of DEHA, the analogous phthalic acid was not the major in vitro metabolite of DEHP. Our preliminary data for 144 adults with no known exposure to DEHA suggests that adipic acid is also the main in vivo urinary metabolite, while MEHA, MEHHA, and MEOHA are only minor metabolites. Therefore, the use of these specific metabolites for assessing the exposure of DEHA may be limited to highly exposed populations.

In Vitro Dermal Absorption of Di(2-ethylhexyl) adipate (DEHA) in a Roll-On Deodorant Using Human Skin

In vitro dermal absorption experiments were conducted using a roll-on deodorant that contains 1.56% di(2-ethylhexyl) adipate (DEHA), a plasticizer widely used in consumer products. Human skin specimens were fitted in Bronaugh flow-through Teflon diffusion cells. The diffusion cells were maintained at 32°C to reflect the skin temperature. Two amounts (low dose: 5 mg of the product; high dose: 100 mg) were applied, in triplicate, each on four different human skins. DEHA was determined in the receiver solution at 6-h intervals, using headspace solid-phase microextraction gas chromatography–mass spectrometry (GC-MS). After 24 h, the experiment was terminated and masses of DEHA in the skin depot, skin wash, and upper and lower chambers of the diffusion cell were determined. A significant portion of applied DEHA, 28% in the low amount application and 34% in the high one, was found in the skin depot. In comparison, only 0.04% and 0.002% of applied DEHA were found in the receiver solutions for the low and high doses, respectively. Under our experimental conditions, an apparent steady-state flux of low DEHA mass penetrating from skin into the receiver solution was observed with a penetration rate of 2.2 ng/cm2/h for both the low and high doses. The average mass recovery was 81% for the low dose application and 56% for the high dose.

Phthalate and di-(2-ethylhexyl) adipate (DEHA) intake by German infants based on the results of a duplicate diet study and biomonitoring data (INES 2)

Phthalates as well as di-(2-ethylhexyl) adipate (DEHA) are used as plasticizers in diverse applications and are of toxicological concern. The study was conducted with a study population of 25 German subjects aged between 15 and 21 months. Overall, 16 phthalates and DEHA were measured by gas chromatography-mass spectrometry in a total of 171 duplicate diet samples collected over 7 consecutive days, and 20 phthalate metabolites were analyzed in the urine samples collected over 7 consecutive days using a liquid chromatography-tandem mass spectrometry method. The median "high" daily dietary intake based on 95th percentiles was 4.66 μg/kg b.w. for di-2-ethylhexyl phthalate (DEHP), 1.03 μg/kg b.w. for di-isobutyl phthalate (DiBP), and 0.70 μg/kg b.w. for di-n-butyl phthalate (DnBP), and 1.0 μg/kg b.w. for DEHA. The "high" daily total intake from biomonitoring data was 4.9 μg/kg b.w. for DEHP, 2.2 μg/kg b.w. for DnBP, 3.9 μg/kg b.w. for DiBP, and 2.6 μg/kg b.w. for di-isononyl phthalate. The comparison of the two intake estimates indicates that the dominant intake source of DEHP was food ingestion, whereas other sources considerably contributed to the total intake of other phthalates. Using our "high" intake scenario, none of the analyzed phthalates reached the recommended tolerable daily intake levels.

A generic emission model to predict release of organic substances from materials in consumer goods

Organic chemicals may be released when consumer goods are used, contributing to environmental and human levels of potentially hazardous chemicals. A generic model was developed to predict emissions of organic chemicals from various materials in consumer products. The model involved three modules, which each predict a key parameter needed to calculate the mass of individual chemicals emitted. Partition coefficients between a material and the surrounding air were predicted using Abraham solvation parameters, diffusion coefficients in materials were calculated using the Piringer equation, and convective mass transfer coefficients were evaluated by applying the Chilton–Colburn analogy. The calculated emission rates from predicted parameters were evaluated and agreed well with literature data. The release of plasticizers from vinyl flooring used in Sweden was calculated to demonstrate the utility of the generic model. The estimated emitted masses of di(2-ethylhexyl)phthalate (DEHP), di-iso-nonylphthalate (DINP), and 1,2-cyclohexanedicarboxylic acid di-iso-nonyl ester (DINCH) in 2012 were 210kg, 40kg, and 3.6kg respectively. Emissions from vinyl flooring were estimated for the period 1990 to 2035 and it was shown that the recent substitution of DEHP with DINP will help to reduce plasticizer emissions. Model calculations for alternative plasticizers revealed that DINCH would yield similar emissions to DINP, whereas use of diethyl hexyl-iso-sorbide or diethyl hexyl adipate would result in higher emissions.

Age- and tanner stage-specific pediatric reference intervals for 7 sex hormones in healthy Canadian children and youth

Plasticizers are chemical compounds used to increase the softness and fluidity of polymer materials. Phthalate compounds constitute the most common class of compounds used as plasticizers. However, phthalate plasticizers, especially the predominant di(2-ethylhexyl)phthalate, have been shown to have adverse effects on environment and human health. Hence, efforts have been made to use safer and environmentally friendly alternate non-phthalate plasticizers in industrial applications. The present study involves structural binding studies on endocrine disrupting potential of three high volume alternate plasticizer compounds, i.e., di-(2-ethylhexyl) adipate (DEHA), acetyl tributyl citrate (ATBC) and 2,2,4-trimethyl 1,3-pentanediol diisobutyrate (TPIB) with sex hormone binding globulin (SHBG). This study showed that DEHA, ATBC and TPIB bind in the ligand binding pocket of SHBG and the structural binding results suggested that the three alternate plasticizers may interfere in the steroid binding of SHBG and thus may cause dysfunction in sex steroid homeostasis.

Optimization of the volume fraction of the NAPL, silicone oil, and biodegradation kinetics of toluene and DMDS in a TPPB

The volume ratio between Non-Aqueous Phase Liquid (NAPL) and water was optimised in order to remove the two hydrophobic volatile organic compounds (VOCs), toluene and dimethyldisulfide (DMDS). Biological oxygen demand after 5 days (BOD5) measurements showed that ratios ranging from 20 to 30% of silicone oil in water enabled optimal removal of both selected substrates, certainly due to a high adhesion of microorganisms at the interface and a high O2 consumption to metabolize pollutants. The removal of these compounds was then efficiently carried out in batch cultures in a Two-Phase Partitioning Bioreactor (TPPB) containing 25% silicone oil. If compared to the results obtained in the absence of NAPL, its presence led to 62 and 107% improvement of the biodegradation rate (global removal rate) for toluene and DMDS respectively. In addition silicone oil was a more efficient NAPL than di-ethylhexyladipate (DEHA), since biodegradation rates were 0.17 and 0.95gm3h−1 for toluene in 25% DEHA and silicone oil respectively. The use of silicone oil as NAPL led to removal yields close to 90 and 75% for toluene and DMDS respectively, and hence to the complete removal of residual VOC if losses by stripping were taken into account, showing the efficiency of TPPB containing silicone oil for the removal of these compounds.