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Yoshii S, Hiki K, Watanabe H, Yamamoto H, Endo S. Freely dissolved concentration profile and Hyalella azteca toxicity of cationic surfactant C 12-benzalkonium in spiked-sediment toxicity test. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 866:161226. [PMID: 36586690 DOI: 10.1016/j.scitotenv.2022.161226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/19/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023]
Abstract
The freely dissolved concentrations (Cfree) have been considered a useful metric for exposure of aquatic organisms to organic contaminants. However, Cfree for cationic surfactants has rarely been measured, and its use in sediment toxicity tests has not been evaluated. In this study, Cfree of the cationic surfactant benzyldodecyldimethylammonium (C12-benzalkonium; C12-BAC) in water-only and spiked-sediment toxicity tests with the amphipod Hyalella azteca was analyzed using a passive sampling method. Polyacrylate-coated glass fibers were adopted as the passive sampler. Sorption isotherms of C12-BAC to the polyacrylate fibers were measured in chemical conditions comparable to those of the toxicity tests and used for Cfree calculation in both tests. Detailed concentration analysis in the sediment toxicity test demonstrated a high concentration gradient of C12-BAC between sediment and overlying water; Cfree in pore water was 17-78 times higher than Cfree in overlying water and was 7.2-13 times higher than Cfree at the sediment-water interface. The 50 % lethal concentration and bioconcentration factor of H. azteca obtained in the water-only test (23 μg/L and 140 ± 70 L/kg-wet, respectively) agreed with those calculated based on Cfree in pore water in the sediment test (49 μg/L and 140 ± 90 L/kg-wet, respectively), indicating that H. azteca is exposed mainly to the freely dissolved fraction in pore water. We concluded that Cfree in pore water is a useful exposure metric for H. azteca to cationic surfactants.
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Affiliation(s)
- Sakura Yoshii
- Health and Environmental Risk Division, National Institute for Environmental Studies, 305-8506 Onogawa 16-2, Tsukuba, Ibaraki, Japan.
| | - Kyoshiro Hiki
- Health and Environmental Risk Division, National Institute for Environmental Studies, 305-8506 Onogawa 16-2, Tsukuba, Ibaraki, Japan
| | - Haruna Watanabe
- Health and Environmental Risk Division, National Institute for Environmental Studies, 305-8506 Onogawa 16-2, Tsukuba, Ibaraki, Japan
| | - Hiroshi Yamamoto
- Health and Environmental Risk Division, National Institute for Environmental Studies, 305-8506 Onogawa 16-2, Tsukuba, Ibaraki, Japan
| | - Satoshi Endo
- Health and Environmental Risk Division, National Institute for Environmental Studies, 305-8506 Onogawa 16-2, Tsukuba, Ibaraki, Japan
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2
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Wang Y, Slotsbo S, Damgaard CF, Holmstrup M. Influence of Soil Moisture on Bioaccumulation, Growth, and Recruitment of Folsomia candida Exposed to Phenanthrene-Polluted Soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:3085-3094. [PMID: 36790897 DOI: 10.1021/acs.est.2c07497] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Climate change has resulted in an increased occurrence of summer droughts in large parts of the world. Low soil moisture has marked impacts on the physiology of soil invertebrates and lowers degradation rates of organic contaminants in soil. Polycyclic aromatic hydrocarbons (PAHs) are hydrophobic contaminants that readily accumulate in the lipids of soil organisms. Here, we exposed springtails (Collembola, small soil living arthropods) to phenanthrene (a common PAH) in combination with a range of soil water contents to investigate the combined effects of these factors on the bioaccumulation, survival, recruitment, and body growth in a full factorial experiment. The results showed that phenanthrene up to 60 mg/kg dry soil had moderate effects on survival (<20%), whereas dry soil (4% soil water content) caused approximately 60% mortality. The bioaccumulation of phenanthrene increased almost 3-fold when soil water content decreased from 22 to 4%. We observed a joint effect of low soil water content and phenanthrene on recruitment, suggesting a synergistic interaction. The recruitment EC50 values of phenanthrene decreased from approximately 40 mg/kg dry soil at 22% soil water content to approximately 10 mg/kg dry soil at 12% soil water content. Our results show that the effects of phenanthrene are more pronounced in dry soil partly because bioaccumulation is enhanced when soils become dry.
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Affiliation(s)
- Yang Wang
- Section for Terrestrial Ecology, Department of Ecoscience, Aarhus University, Building 1120, C.F. Møllers Allé 4, 8000 Aarhus C, Denmark
| | - Stine Slotsbo
- Section for Terrestrial Ecology, Department of Ecoscience, Aarhus University, Building 1120, C.F. Møllers Allé 4, 8000 Aarhus C, Denmark
| | - Christian Frølund Damgaard
- Section for Terrestrial Ecology, Department of Ecoscience, Aarhus University, Building 1120, C.F. Møllers Allé 4, 8000 Aarhus C, Denmark
| | - Martin Holmstrup
- Section for Terrestrial Ecology, Department of Ecoscience, Aarhus University, Building 1120, C.F. Møllers Allé 4, 8000 Aarhus C, Denmark
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3
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Schmidt SN, Burgess RM. Evaluating Polymeric Sampling as a Tool for Predicting the Bioaccumulation of Polychlorinated Biphenyls by Fish and Shellfish. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:9729-9741. [PMID: 32585088 PMCID: PMC7478847 DOI: 10.1021/acs.est.9b07292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Recent research has shown that polymeric sampling data generally can predict the bioaccumulation of hydrophobic organic contaminants by benthic and sessile invertebrates. Based on literature data, this review evaluated polymeric sampling as a tool for predicting the bioaccumulation of polychlorinated biphenyls (PCBs) by pelagic and mobile fish and shellfish. Lipid-normalized concentrations (CL) were linked to corresponding equilibrium polymer concentrations (CP) to evaluate the (1) correlation between CL and CP, (2) accuracy when using CP as surrogates for CL, (3) effects of experimental variables on these results, and (4) implications associated with this approach. Generally, strong positive log-log linear correlations existed between CL and CP, meaning that increasing bioaccumulation was well-reflected by increasing polymer accumulation. Further, the majority of the regression lines, as well as individual CL to CP ratios, were within a factor of 10 from the hypothetical 1:1 relationship, suggesting that polymers accumulated concentrations comparable to body residues in fish and shellfish. Interestingly, overall stronger correlations and lower CL to CP ratios resulted when CP were based on sediment compared to water column-deployed samplers. These findings provide a tool for environmental managers when assessing and managing risk associated with PCB-contaminated sediments and waters in protecting vulnerable fish and shellfish species.
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Affiliation(s)
- Stine N. Schmidt
- National Research Council, US Environmental Protection Agency, Office of Research and Development, Atlantic Coastal Environmental Sciences Division, Narragansett, Rhode Island, USA
| | - Robert M. Burgess
- US Environmental Protection Agency, Office of Research and Development, Atlantic Coastal Environmental Sciences Division, Narragansett, Rhode Island, USA
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4
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Timmer N, Gore D, Sanders D, Gouin T, Droge STJ. Application of seven different clay types in sorbent-modified biodegradability studies with cationic biocides. CHEMOSPHERE 2020; 245:125643. [PMID: 31877460 DOI: 10.1016/j.chemosphere.2019.125643] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 12/10/2019] [Accepted: 12/11/2019] [Indexed: 06/10/2023]
Abstract
The cationic surfactants cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC) can exert inhibitory effects on micro-organisms responsible for their biodegradation. However, under environmentally relevant exposure scenarios the presence of and sorption to organic and inorganic matter can lead to significant reduction of inhibitory effects. In our studies we investigated silica gel and seven clays as inert sorbents to mitigate these inhibitory effects in a 28 day manometric respirometry biodegradation test. CTAB was not inhibitory to the used inoculum, but we did observe that seven out of eight sorbents increased maximum attainable biodegradation, and four out of eight decreased the lag phase. The strongly inhibitory effect of CPC was successfully mitigated by most sorbents, with five out of eight allowing >50% biodegradation within 28 days. Results further indicate that bioaccessibility of the sorbed fractions in the stirred manometric test systems was higher than in calmly shaken headspace test systems. Bioaccessibility might also be limited depending on characteristics of test chemical and sorbent type, with montmorillonite and bentonite apparently providing the lowest level of bioaccessibility with CPC. Clay sorbents can thus be used as environmentally relevant sorbents to mitigate potential inhibitory effects of test chemicals, but factors that impede bioaccessibility should be considered. In addition to apparently increased bioaccessibility due to stirring, the automated manometric respirometry test systems give valuable and highly cost-effective insights into lag phase and biodegradation kinetics; information that is especially relevant for test chemicals of gradual biodegradability.
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Affiliation(s)
- Niels Timmer
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, 3508 TD, the Netherlands; Department Discovery and Environmental Sciences, Charles River Laboratories Den Bosch BV, 's-Hertogenbosch, 5231 DD, the Netherlands
| | - David Gore
- Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, MK44 1LQ, Bedfordshire, UK
| | - David Sanders
- Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, MK44 1LQ, Bedfordshire, UK
| | - Todd Gouin
- Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, MK44 1LQ, Bedfordshire, UK
| | - Steven T J Droge
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, 3508 TD, the Netherlands; Department Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, P.O. Box 94248, 1090 GE, Amsterdam, the Netherlands.
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5
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Yan Y, Yang S, Zhou Y, Song Y, Huang J, Liu Z, Wang Y, Wei S. Estimating the national burden of mild intellectual disability in children exposed to dietary lead in China. ENVIRONMENT INTERNATIONAL 2020; 137:105553. [PMID: 32086077 DOI: 10.1016/j.envint.2020.105553] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 01/13/2020] [Accepted: 02/04/2020] [Indexed: 06/10/2023]
Abstract
The effects of lead as a dietary pollutant remain a global public health concern that needs urgent resolution. Children are highly susceptible to the adverse outcomes of lead pollution, as even low levels of lead may cause irreversible damage to intellectual development. Since several sources of lead exposure are present in the environment, it is necessary to identify the attributable burden of lead-related diseases arising from different exposure sources. In the present study, we used epidemiological data from studies around the nation to estimate the burden of mild intellectual disability (MID) attributed to lead exposure sources by using disability-adjusted life years (DALYs). To this end, a dose-response approach was used and a model comprising three components was established: exposure, dose-response, and DALYs module. In Chinese children aged 0-6 years, blood lead levels (BLLs) of 5.34 ± 3.09 μg/dL resulted in a MID incidence rate of 12.84 cases per 1000 children, with an estimated burden of disease (BoD) of 42.23 DALYs per 1000 children. Owing to dietary lead exposure, 36.64 healthy life years per 1000 children were lost, which was notably higher than the outcomes associated with exposure from other sources. This was consistent with the result that dietary exposure was the main contributor to children's lead exposure, accounting for 86.76%. According to the regional distribution based on the existing literature, the areas in China with higher BLLs were Heilongjiang, Shanxi, and Jiangxi. Our findings provided the information for lead risk management decisions and policies making.
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Affiliation(s)
- Yizhong Yan
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Sulian Yang
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yujing Zhou
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yan Song
- National Food Safety Risk Assessment Center, Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 10022, China.
| | - Jiao Huang
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zhaoping Liu
- National Food Safety Risk Assessment Center, Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 10022, China.
| | - Yibaina Wang
- National Food Safety Risk Assessment Center, Key Laboratory of Food Safety Risk Assessment, Ministry of Health, Beijing 10022, China.
| | - Sheng Wei
- School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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6
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Timmer N, Gore D, Sanders D, Gouin T, Droge STJ. Sorbent-modified biodegradation studies of the biocidal cationic surfactant cetylpyridinium chloride. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 182:109417. [PMID: 31302333 DOI: 10.1016/j.ecoenv.2019.109417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 06/29/2019] [Accepted: 07/03/2019] [Indexed: 06/10/2023]
Abstract
Biodegradability studies for the cationic surfactant cetylpyridinium chloride (CPC) are hampered by inhibitory effects on inoculum at prescribed test concentrations (10-20 mg organic carbon/L). In this study, we used 14C labeled CPC in the 28 d Headspace Test (OECD 310) and demonstrated that CPC was readily biodegradable (10->60% mineralization within a 10 day window) at test concentrations 0.006-0.3 mg/L with CPC as single substrate. Biodegradation efficiency was comparable over this concentration range. CPC inhibited degradation at 1 mg/L and completely suppressed inoculum activity at 3 mg/L. In an extensive sorbent modified biodegradation study we evaluated the balance between CPC bioaccessibility and toxicity. A non-inhibitory concentration of 0.1 mg/L CPC was readily biodegradable with 83% sorbed to SiO2, while biodegradation was slower when 96% was sorbed. SiO2 mitigated inhibitory effects of 1 mg/L CPC, reaching >60% biodegradation within 28 d; inhibitory effects were also mitigated by addition of commercial clay powder (illite) but this was primarily reflected by a reduced lag phase. At 10 mg/L CPC SiO2 was still able to mitigate inhibitory effects, but bioaccessibility seemed limited as only 20% biodegradation was reached. Illite limited bioaccessibility more strongly and was not able to sustain biodegradation at 10 mg/L CPC.
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Affiliation(s)
- Niels Timmer
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, 3508, TD, the Netherlands
| | - David Gore
- Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, MK44 1LQ. Bedfordshire, UK
| | - David Sanders
- Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, MK44 1LQ. Bedfordshire, UK
| | - Todd Gouin
- Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, MK44 1LQ. Bedfordshire, UK
| | - Steven T J Droge
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, 3508, TD, the Netherlands; Department Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, PO Box 94248, 1090 GE Amsterdam, the Netherlands.
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7
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Groothuis FA, Timmer N, Opsahl E, Nicol B, Droge STJ, Blaauboer BJ, Kramer NI. Influence of in Vitro Assay Setup on the Apparent Cytotoxic Potency of Benzalkonium Chlorides. Chem Res Toxicol 2019; 32:1103-1114. [PMID: 31012305 PMCID: PMC6584903 DOI: 10.1021/acs.chemrestox.8b00412] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The nominal concentration
is generally used to express concentration–effect
relationships in in vitro toxicity assays. However, the nominal concentration
does not necessarily represent the exposure concentration responsible
for the observed effect. Surfactants accumulate at interphases and
likely sorb to in vitro system components such as serum protein and
well plate plastic. The extent of sorption and the consequences of
this sorption on in vitro readouts is largely unknown for these chemicals.
The aim of this study was to demonstrate the effect of sorption to
in vitro components on the observed cytotoxic potency of benzalkonium
chlorides (BAC) varying in alkyl chain length (6–18 carbon
atoms, C6–18) in a basal cytotoxicity assay with
the rainbow trout gill cell line (RTgill-W1). Cells were exposed for
48 h in 96-well plates to increasing concentration of BACs in exposure
medium containing 0, 60 μM bovine serum albumin (BSA) or 10%
fetal bovine serum (FBS). Before and after exposure, BAC concentrations
in exposure medium were analytically determined. Based on freely dissolved
concentrations at the end of the exposure, median effect concentrations
(EC50) decreased with increasing alkyl chain length up
to 14 carbons. For BAC with alkyl chains of 12 or more carbons, EC50’s based on measured concentrations after exposure
in supplement-free medium were up to 25-times lower than EC50’s calculated using nominal concentrations. When BSA or FBS
was added to the medium, a decrease in cytotoxic potency of up to
22 times was observed for BAC with alkyl chains of eight or more carbons.
The results of this study emphasize the importance of expressing the
in vitro readouts as a function of a dose metric that is least influenced
by assay setup to compare assay sensitivities and chemical potencies.
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Affiliation(s)
- Floris A Groothuis
- Institute for Risk Assessment Sciences , Utrecht University , PO Box 80177, 3508 TD Utrecht , The Netherlands
| | - Niels Timmer
- Institute for Risk Assessment Sciences , Utrecht University , PO Box 80177, 3508 TD Utrecht , The Netherlands
| | - Eystein Opsahl
- Institute for Risk Assessment Sciences , Utrecht University , PO Box 80177, 3508 TD Utrecht , The Netherlands
| | - Beate Nicol
- Safety & Environmental Assurance Centre , Unilever U.K. , Colworth Science Park, Sharnbrook, Bedford MK44 1LQ , United Kingdom
| | - Steven T J Droge
- Institute for Risk Assessment Sciences , Utrecht University , PO Box 80177, 3508 TD Utrecht , The Netherlands
| | - Bas J Blaauboer
- Institute for Risk Assessment Sciences , Utrecht University , PO Box 80177, 3508 TD Utrecht , The Netherlands
| | - Nynke I Kramer
- Institute for Risk Assessment Sciences , Utrecht University , PO Box 80177, 3508 TD Utrecht , The Netherlands
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8
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Chen Y, Geurts M, Sjollema SB, Kramer NI, Hermens JLM, Droge STJ. Acute toxicity of the cationic surfactant C12-benzalkonium in different bioassays: how test design affects bioavailability and effect concentrations. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2014; 33:606-15. [PMID: 24273010 DOI: 10.1002/etc.2465] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 09/25/2013] [Accepted: 11/14/2013] [Indexed: 05/19/2023]
Abstract
Using an ion-exchange-based solid-phase microextraction (SPME) method, the freely dissolved concentrations of C12-benzalkonium were measured in different toxicity assays, including 1) immobilization of Daphnia magna in the presence or absence of dissolved humic acid; 2) mortality of Lumbriculus variegatus in the presence or absence of a suspension of Organisation for Economic Co-Operation and Development (OECD) sediment; 3) photosystem II inhibition of green algae Chlorella vulgaris; and 4) viability of in vitro rainbow trout gill cell line (RTgill-W1) in the presence or absence of serum proteins. Furthermore, the loss from chemical adsorption to the different test vessels used in these tests was also determined. The C12-benzalkonium sorption isotherms to the different sorbent phases were established as well. Our results show that the freely dissolved concentration is a better indicator of the actual exposure concentration than the nominal or total concentration in most test assays. Daphnia was the most sensitive species to C12-benzalkonium. The acute Daphnia and Lumbriculus tests both showed no enhanced toxicity from possible ingestion of sorbed C12-benzalkonium in comparison with water-only exposure, which is in accordance with the equilibrium partitioning theory. Moreover, the present study demonstrates that commonly used sorbent phases can strongly affect bioavailability and observed effect concentrations for C12-benzalkonium. Even stronger effects of decreased actual exposure concentrations resulting from sorption to test vessels, cells, and sorbent phases can be expected for more hydrophobic cationic surfactants.
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Affiliation(s)
- Yi Chen
- Institute for Risk Assessment Sciences, Utrecht University, The Netherlands
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9
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Stalter D, Dutt M, Escher BI. Headspace-free setup of in vitro bioassays for the evaluation of volatile disinfection by-products. Chem Res Toxicol 2013; 26:1605-14. [PMID: 24117097 DOI: 10.1021/tx400263h] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The conventional setup of in vitro bioassays in microplates does not prevent the loss of volatile compounds, which hampers the toxicological characterization of waterborne volatile disinfection by-products (DBPs). To minimize the loss of volatile test chemicals, we adapted four in vitro bioassays to a headspace-free setup using eight volatile organic compounds (four trihalomethanes, 1,1-dichloroethene, bromoethane, and two haloacetonitriles) that cover a wide range of air-water partition coefficients. The nominal effect concentrations of the test chemicals decreased by up to three orders of magnitude when the conventional setup was changed to a headspace-free setup for the bacterial cytotoxicity assay using bioluminescence inhibition of Vibrio fischeri. The increase of apparent sensitivity correlated significantly with the air-water partition coefficient. Purge and trap GC/MS analysis revealed a reduced loss of dosed volatile compounds in the headspace free setup (78-130% of nominal concentration) compared to a substantial loss in the conventional set up (2-13% of the nominal concentration). The experimental effect concentrations converged with the headspace-free setup to the effect concentrations predicted by a QSAR model, confirming the suitability of the headspace-free approach to minimize the loss of volatile test chemicals. The analogue headspace-free design of the bacterial bioassays for genotoxicity (umuC assay) and mutagenicity (Ames fluctuation assay) increased the number of compounds detected as genotoxic or mutagenic from one to four and zero to two, respectively. In a bioassay with a mammalian cell line applied for detecting the induction of the Nrf-2-mediated oxidative stress response (AREc32 assay), the headspace-free setup improved the apparent sensitivity by less than one order of magnitude, presumably due to the retaining effect of the serum components in the medium, which is also reflected in the reduced aqueous concentrations of compounds. This study highlights the importance of adapting bioanalytical test setups when volatile/semivolatile compounds are present in the sample to avoid the loss of chemicals and thus to avoid underestimating the toxicity of mixtures and complex environmental samples.
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Affiliation(s)
- Daniel Stalter
- National Research Centre for Environmental Toxicology (Entox), The University of Queensland , 39 Kessels Road, Brisbane Qld 4108, Australia
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10
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Schmidt SN, Smith KEC, Holmstrup M, Mayer P. Uptake and toxicity of polycyclic aromatic hydrocarbons in terrestrial springtails--studying bioconcentration kinetics and linking toxicity to chemical activity. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2013; 32:361-369. [PMID: 23147567 DOI: 10.1002/etc.2051] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 08/20/2012] [Accepted: 09/05/2012] [Indexed: 06/01/2023]
Abstract
Passive dosing applies a polymer loaded with test compound(s) to establish and maintain constant exposure in laboratory experiments. Passive dosing with the silicone poly(dimethylsiloxane) was used to control exposure of the terrestrial springtail Folsomia candida to six polycyclic aromatic hydrocarbons (PAHs) in bioconcentration and toxicity experiments. Folsomia candida could move freely on the PAH-loaded silicone, resulting in exposure via air and direct contact. The bioconcentration kinetics indicated efficient uptake of naphthalene, anthracene, and pyrene through air and (near) equilibrium partitioning of these PAHs to lipids and possibly the waxy layer of the springtail cuticle. Toxicities of naphthalene, phenanthrene, and pyrene were related to chemical activity, which quantifies the energetic level and drives spontaneous processes including diffusive biouptake. Chemical activity-response relationships yielded effective lethal chemical activities (La50s) well within the expected range for baseline toxicity (0.01-0.1). Effective lethal body burdens for naphthalene and pyrene exceeded the expected range of 2 to 8 mmol kg(-1) fresh weight, which again indicated the waxy layer to be a sorbing phase. Finally, chemical activities were converted into equilibrium partitioning concentrations in lipids yielding effective lethal concentrations for naphthalene and phenanthrene in good correspondence with the lethal membrane burden for baseline toxicity (40-160 mmol kg(-1) lipid). Passive dosing was a practical approach for tightly controlling PAH exposure, which in turn provided new experimental possibilities and findings.
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Affiliation(s)
- Stine Nørgaard Schmidt
- Department of Environmental Science, Faculty of Science and Technology, Aarhus University, Roskilde, Denmark
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11
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Chen Y, Droge ST, Hermens JL. Analyzing freely dissolved concentrations of cationic surfactant utilizing ion-exchange capability of polyacrylate coated solid-phase microextraction fibers. J Chromatogr A 2012; 1252:15-22. [DOI: 10.1016/j.chroma.2012.06.080] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Accepted: 06/22/2012] [Indexed: 10/28/2022]
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12
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Booij P, Lamoree MH, Leonards PEG, Cenijn PH, Klamer HJC, van Vliet LA, Akerman J, Legler J. Development of a polydimethylsiloxane film-based passive dosing method in the in vitro DR-CALUX® assay. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2011; 30:898-904. [PMID: 21191882 DOI: 10.1002/etc.453] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 05/12/2010] [Accepted: 10/20/2010] [Indexed: 05/30/2023]
Abstract
In bioassays, exposure concentrations of test compounds are usually expressed as nominal concentrations. As a result of various processes, such as adsorption, degradation, or uptake, the actual freely dissolved concentration of the test compound may differ from the nominal concentration. The goal of the present study was to develop a method to dose passively the freely dissolved fraction of organic chemicals in an in vitro bioassay with adherent cells. To this end, a polydimethylsiloxane (PDMS) film-based method was developed for a reporter gene assay for dioxin-like compounds in a rat liver cell line. Polydimethylsiloxane films loaded with test compounds ensure that the concentration during exposure is in equilibrium and that the ratio between the concentration on the film and the concentration in medium is constant. Benzo[k]fluoranthene (BkF) was used as a model compound to develop the passive dosing method in transwell plates, which was further tested with a complex mixture, i.e., an extract prepared from a contaminated sediment. A higher dioxin-like activity was found when extracts were dosed by passive dosing with PDMS than when directly added to medium. Comparison with analysis of the concentration of BkF in medium shows that passive dosing of individual chemicals may not be necessary if freely dissolved concentrations are known. Use of PDMS for passive dosing of complex samples may represent a more realistic method for exposure in in vitro bioassays.
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Affiliation(s)
- Petra Booij
- Institute for Environmental Studies, VU University Amsterdam, Amsterdam, The Netherlands.
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13
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Voutchkova AM, Osimitz TG, Anastas PT. Toward a Comprehensive Molecular Design Framework for Reduced Hazard. Chem Rev 2010; 110:5845-82. [DOI: 10.1021/cr9003105] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Adelina M. Voutchkova
- Center for Green Chemistry and Green Engineering, Yale University, New Haven, Connecticut 06511, and Science Strategies LLC, 600 East Water St., Charlottesville, VA 22902
| | - Thomas G. Osimitz
- Center for Green Chemistry and Green Engineering, Yale University, New Haven, Connecticut 06511, and Science Strategies LLC, 600 East Water St., Charlottesville, VA 22902
| | - Paul T. Anastas
- Center for Green Chemistry and Green Engineering, Yale University, New Haven, Connecticut 06511, and Science Strategies LLC, 600 East Water St., Charlottesville, VA 22902
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The usefulness of total concentrations and pore water concentrations of pesticides in soil as metrics for the assessment of ecotoxicological effects ‐ Scientific Opinion of the Panel on Plant Protection Products and their Residues (PPR). EFSA J 2009. [DOI: 10.2903/j.efsa.2009.922] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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