1
|
Islam F, Wang J, Farooq MA, Khan MSS, Xu L, Zhu J, Zhao M, Muños S, Li QX, Zhou W. Potential impact of the herbicide 2,4-dichlorophenoxyacetic acid on human and ecosystems. ENVIRONMENT INTERNATIONAL 2018; 111:332-351. [PMID: 29203058 DOI: 10.1016/j.envint.2017.10.020] [Citation(s) in RCA: 171] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/18/2017] [Accepted: 10/20/2017] [Indexed: 05/03/2023]
Abstract
The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is applied directly to aquatic and conventional farming systems to control weeds, and is among the most widely distributed pollutants in the environment. Non-target organisms are exposed to 2,4-D via several ways, which could produce toxic effects depending on the dose, frequency of exposure, and the host factors that influence susceptibility and sensitivity. An increasing number of experimental evidences have shown concerns about its presence/detection in the environment, because several investigations have pointed out its potential lethal effects on non-target organisms. In this review, we critically evaluated the environmental fate and behavior of 2,4-D along with its eco-toxicological effects on aquatic, plants and human life to provide concise assessment in the light of recently published reports. The findings demonstrate that 2,4-D is present in a low concentration in surface water of regions where its usage is high. The highest concentrations of 2,4-D were detected in soil, air and surface water surrounded by crop fields, which suggest that mitigation strategies must be implanted locally to prevent the entry of 2,4-D into the environment. A general public may have frequent exposure to 2,4-D due to its wide applications at home lawns and public parks, etc. Various in vivo and in vitro investigations suggest that several species (or their organs) at different trophic levels are extremely sensitive to the 2,4-D exposure, which may explain variation in outcomes of reported investigations. However, implications for the prenatal exposure to 2,4-D remain unknown because 2,4-D-induced toxicity thresholds in organism have only been derived from juveniles or adults. In near future, introduction of 2,4-D resistant crops will increase its use in agriculture, which may cause relatively high and potentially unsafe residue levels in the environment. The recent findings indicate the urgent need to further explore fate, accumulation and its continuous low level exposure impacts on the environment to generate reliable database which is key in drafting new regulation and policies to protect the population from further exposure.
Collapse
Affiliation(s)
- Faisal Islam
- College of Agriculture and Biotechnology, Zhejiang Key Laboratory of Crop Germplasm, Institute of Crop Science, Zhejiang University, Hangzhou 310058, China
| | - Jian Wang
- College of Agriculture and Biotechnology, Zhejiang Key Laboratory of Crop Germplasm, Institute of Crop Science, Zhejiang University, Hangzhou 310058, China
| | - Muhammad A Farooq
- College of Agriculture and Biotechnology, Zhejiang Key Laboratory of Crop Germplasm, Institute of Crop Science, Zhejiang University, Hangzhou 310058, China; Institute of Pure and Applied Biology, Bahauddin Zakariya University, Multan 60800, Pakistan
| | - Muhammad S S Khan
- College of Agriculture and Biotechnology, Zhejiang Key Laboratory of Crop Germplasm, Institute of Crop Science, Zhejiang University, Hangzhou 310058, China
| | - Ling Xu
- Zhejiang Key Laboratory of Plant Secondary Metabolism and Regulation, College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jinwen Zhu
- College of Agriculture and Biotechnology, Zhejiang Key Laboratory of Crop Germplasm, Institute of Crop Science, Zhejiang University, Hangzhou 310058, China
| | - Min Zhao
- Zhejiang Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection, Wenzhou University, Wenzhou 325035, China
| | - Stéphane Muños
- Laboratoire des Interactions Plantes Micro-organismes, Université de Toulouse, CNRS-INRA, 441-2594, France
| | - Qing X Li
- Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu 96822, USA
| | - Weijun Zhou
- College of Agriculture and Biotechnology, Zhejiang Key Laboratory of Crop Germplasm, Institute of Crop Science, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
2
|
von Stackelberg K. A Systematic Review of Carcinogenic Outcomes and Potential Mechanisms from Exposure to 2,4-D and MCPA in the Environment. J Toxicol 2013; 2013:371610. [PMID: 23533401 PMCID: PMC3600329 DOI: 10.1155/2013/371610] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 05/18/2012] [Accepted: 07/11/2012] [Indexed: 12/21/2022] Open
Abstract
Chlorophenoxy compounds, particularly 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxy)acetic acid (MCPA), are amongst the most widely used herbicides in the United States for both agricultural and residential applications. Epidemiologic studies suggest that exposure to 2,4-D and MCPA may be associated with increased risk non-Hodgkins lymphoma (NHL), Hodgkin's disease (HD), leukemia, and soft-tissue sarcoma (STS). Toxicological studies in rodents show no evidence of carcinogenicity, and regulatory agencies worldwide consider chlorophenoxies as not likely to be carcinogenic or unclassifiable as to carcinogenicity. This systematic review assembles the available data to evaluate epidemiologic, toxicological, pharmacokinetic, exposure, and biomonitoring studies with respect to key cellular events noted in disease etiology and how those relate to hypothesized modes of action for these constituents to determine the plausibility of an association between exposure to environmentally relevant concentrations of 2,4-D and MCPA and lymphohematopoietic cancers. The combined evidence does not support a genotoxic mode of action. Although plausible hypotheses for other carcinogenic modes of action exist, a comparison of biomonitoring data to oral equivalent doses calculated from bioassay data shows that environmental exposures are not sufficient to support a causal relationship. Genetic polymorphisms exist that are known to increase the risk of developing NHL. The potential interaction between these polymorphisms and exposures to chlorophenoxy compounds, particularly in occupational settings, is largely unknown.
Collapse
Affiliation(s)
- Katherine von Stackelberg
- E Risk Sciences, LLP, 12 Holton Street, Allston, MA 02134, USA
- Harvard Center for Risk Analysis, 401 Park Drive, Landmark 404J, Boston, MA 02215, USA
| |
Collapse
|
3
|
Aronzon CM, Sandoval MT, Herkovits J, Pérez-Coll CS. Stage-dependent toxicity of 2,4-dichlorophenoxyacetic on the embryonic development of a South American toad, Rhinella arenarum. ENVIRONMENTAL TOXICOLOGY 2011; 26:373-81. [PMID: 20112415 DOI: 10.1002/tox.20564] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Revised: 12/03/2009] [Accepted: 12/06/2009] [Indexed: 05/03/2023]
Abstract
The acute and short term chronic toxicity of both the herbicide butyl ester of 2,4-Dichlorophenoxyacetic acid (2,4-D) and a commercial formulation (CF) were evaluated on Rhinella (= Bufo) arenarum embryos at different developmental stages. Adverse effects were analyzed by means of the isotoxicity curves for lethality, malformations, stage-dependent susceptibility, and ultrastructural features. For all experimental conditions, the CF was more toxic, up to 10 times, than the active ingredient, being the open mouth stage (S.21) the most susceptible to the herbicide. For continuous treatment conditions, the early embryonic development was the most susceptible to 2,4-D and the LC50s for 96 and 168 h were 9.06 and 7.76 mg L(-1) respectively. In addition, both the active ingredient and the CF were highly teratogenic, resulting in reduced body size, delayed development, microcephaly, agenesis of gills, and abnormal cellular proliferation processes as the main adverse effects. According to US EPA, 2,4-D in agricultural scenarios may be up to three times higher than the NOEC values for teratogenic effects reported in this study. Therefore, they might represent a risk for amphibians. This study also points out the relevance of reporting the susceptibility of embryos at different developmental stages to both the active ingredient and the CF of agrochemicals in order to protect nontarget organisms.
Collapse
Affiliation(s)
- Carolina M Aronzon
- Programa de Seguridad Química, Instituto de Ciencias Ambientales y Salud (ICAS), Fundación PROSAMA, Paysandú 752, (1405) Buenos Aires, Argentina
| | | | | | | |
Collapse
|
4
|
Fabra A, Giordano W, Rivarola V, Mori G, Castro S, Balegno H. The interaction of 2,4-dichlorophenoxyacetic acid, ribosomes and polyamines in Azospirillum brasilense. Toxicology 1993; 83:19-29. [PMID: 8248945 DOI: 10.1016/0300-483x(93)90088-a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
2,4-Dichlorophenoxyacetic acid (2,4-D) is an herbicide used extensively in agriculture. We had previously determined that 1 mM 2,4-D could inhibit cell growth, DNA and protein synthesis of Azospirillum brasilense. The present work was designed to determine if these alterations are a consequence of 2,4-D action on polyamine biosynthesis and if the protein synthesis inhibition is a result of ribosomal impairment. In this paper we demonstrate that 2,4-D alters the metabolism of polyamines and, thus, affects protein synthesis at the ribosomal level.
Collapse
Affiliation(s)
- A Fabra
- Facultad de Ciencias Exactas, Universidad Nacional de Rio Cuarto, Córdoba, Argentina
| | | | | | | | | | | |
Collapse
|
5
|
Rivarola V, Fabra A, Mori G, Balegno H. In vitro protein synthesis is affected by the herbicide 2,4-dichlorophenoxyacetic acid in Azospirillum brasilense. Toxicology 1992; 73:71-9. [PMID: 1375402 DOI: 10.1016/0300-483x(92)90171-a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The effects of 2,4-dichlorophenoxyacetic acid (2,4-D) on growth and protein, DNA and RNA synthesis of Azospirillum brasilense Cd were studied. At a concentration of 1 mM, 2,4-D inhibited cell growth, an effect that was reversed either by transferring bacteria to a control (2,4-D-free) medium or to a 2,4-D-treated medium supplemented with polyamines. The herbicide also affected in vitro protein synthesis, either when Azospirillum brasilense Cd's own cellular mRNA or an artificial mRNA was used. This effect was also reversed by the addition of polyamines to the 2,4-D-treated medium. Similar results were observed when DNA synthesis was studied in synchronous cultures. Taking into account the effects of this herbicide on animal cells (V.A. Rivarola and H.F. Balegno, Toxicology, 68 (1991) 109) we postulate that the mechanism of action of 2,4-D is similar on both procaryotic and eucaryotic cells, probably acting through the polyamine metabolism.
Collapse
Affiliation(s)
- V Rivarola
- Facultad de Ciencias Exactas, Fisico-Química y Naturales, Universidad Nacional de Río Cuarto, Córdoba, Argentina
| | | | | | | |
Collapse
|