RESUMO

In 1996, a diagnostic study performed in a 16-ha field located in Buenos Aires Province (Argentina), where a chemical industry produced 1,2,3,4,5,6-hexachlorocyclohexane (HCH) from 1960 to 1978, showed contamination with HCH ranging from 10 to 20,000 mg kg-1 dry soil (706.4 mg kg-1 average). For remediation purposes, a forestation plan was put into practice in 1997 employing approximately 12,300 Eucalyptus dunnii seedlings which by 2016 where fully grown into trees that formed a forest where local fauna can be found. Midterm analysis done in 2005, when E. dunnii trees had developed into 8-10 m high trees, indicated that HCH was incorporated into leaves and logs and soil phytoremediation was progressing. Final quantitation analysis of HCH in soil performed in 2016 demonstrated that the 97.2% of the field area was effectively decontaminated with 98.1% overall average efficiency. Thus, this work is the first global example of a successful employment of E. dunnii trees for HCH phytoremediation purposes at field scale. These results may encourage other researchers to test the ability of E. dunnii to phytoremediate soils contaminated with other chlorinated compounds like polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs).

Assuntos

RESUMO

Actinobacteria are well-known degraders of toxic materials that have the ability to tolerate and remove organochloride pesticides; thus, they are used for bioremediation. The biodegradation of organochlorines by actinobacteria has been demonstrated in pure and mixed cultures with the concomitant production of metabolic intermediates including γ-pentachlorocyclohexene (γ-PCCH); 1,3,4,6-tetrachloro-1,4-cyclohexadiene (1,4-TCDN); 1,2-dichlorobenzene (1,2-DCB), 1,3-dichlorobenzene (1,3-DCB), or 1,4-dichlorobenzene (1,4-DCB); 1,2,3-trichlorobenzene (1,2,3-TCB), 1,2,4-trichlorobenzene (1,2,4-TCB), or 1,3,5-trichlorobenzene (1,3,5-TCB); 1,3-DCB; and 1,2-DCB. Chromatography coupled to mass spectrometric detection, especially GC-MS, is typically used to determine HCH-isomer metabolites. The important enzymes involved in HCH isomer degradation metabolic pathways include hexachlorocyclohexane dehydrochlorinase (LinA), haloalkane dehalogenase (LinB), and alcohol dehydrogenase (LinC). The metabolic versatility of these enzymes is known. Advances have been made in the identification of actinobacterial haloalkane dehydrogenase, which is encoded by linB. This knowledge will permit future improvements in biodegradation processes using Actinobacteria. The enzymatic and genetic characterizations of the molecular mechanisms involved in these processes have not been fully elucidated, necessitating further studies. New advances in this area suggest promising results. The scope of this paper encompasses the following: (i) the aerobic degradation pathways of hexachlorocyclohexane (HCH) isomers; (ii) the important genes and enzymes involved in the metabolic pathways of HCH isomer degradation; and (iii) the identification and quantification of intermediate metabolites through gas chromatography coupled to mass spectrometry (GC-MS).

Assuntos

RESUMO

Pesticide helps to enhance agricultural production, however, it significantly affect both socio and environmental entities of a country. In Nigeria, pesticide is widely used, thus its traces have been detected in water, soil and air. Several studies have already indicated that most of the environmental ecology (air, water, and soil) in Nigeria has been contaminated by persistent organic pesticides like organochlorine and organophosphate. Other reasons of high pesticide residues present in Nigeria environment is due to inappropriate dosage applied of pesticides that leaves behind excess. However, its residues are found above safety levels in the air, water, and soil across the nation. Based on previous analysis, it is indicated that 125,000-130,000 metric ton pesticides are being applied annually in Nigeria. Despite banned of some pesticides such as dichlorodiphenyltrichloroethane- and -Hexachlorocyclohexane, they are still being used by farmers in their agricultural production. Many of the Class 1 (high extremely toxic) pesticides are still being used in developing countries like Nigeria. Hence, there is need to sensitize and educate the general public especially the end-users (farmers) particularly on management practices of pesticides. Considering these entire hazardous situations, in this article the history of pesticide used in Nigeria has been reviewed in detail. The article also discussed the effects of pesticide use in Nigerianwaters, soil and on crops. The risk of residual pesticide on agricultural workers, pesticide residue riskpreventive measures by the Federal Government of Nigeria, banned and restricted pesticides in Nigeria,Nigerian Government and its efforts to eliminate persistent organic pesticides in use are also reviewedin details.(AU)

Inseticidas ajudam a aumentar a produção agrícola, no entanto, afetam significativamente a sociedade e o ambiente do país. Na Nigéria, os inseticidas são amplamente utilizados, assim, seus resíduos foram detectados na água, solo e ar. Vários estudos já indicaram que a maior parte dos aspetos ecológicos ambientais (ar, água e solo) na Nigéria tenham sido contaminados por pesticidas orgânicos persistentes como os organoclorados (OCL) e organofosforados (OP). Outro motivo relacionado com a ocorrência de resíduos elevados de inseticidas presentes no meio ambiente na Nigéria é devido às dosagens inadequadas aplicadas de pesticidas que são aplicados em excesso. No entanto, seus resíduos são encontrados acima dos níveis de segurança no ar, água e solo em todo o país. Com base em dados anterior, é observado que 125,000-130,000 toneladas métricas de pesticidas são aplicadas por ano na Nigéria. Apesar da proibição de alguns pesticidas como o DDT (Dicloro-difenil-tricloroetano) e HCH (Hexa-cloro- ciclohexano), eles ainda estão sendo usados pelos agricultores para a produção agrícola. Muitos dos Classe 1 pesticidas (extremamente tóxicos) ainda estão sendo usados nos países em desenvolvimento como a Nigéria. Assim, não há necessidade de sensibilizar e educar o público em geral, especialmente os usuários finais (agricultores) em particular sobre as práticas para o manejo dos inseticidas. Considerando estas situações de perigo real, neste artigo o histórico de uso de inseitidas naNigéria foi estudo em detalhe. O artigo também discute os efeitos da utilização de inseticidas nas águas,no solo e nas culturas. O risco de contaminação para os trabalhadores rurais as medidas preventivaspara controlar risco de resíduos adotadas pelo Governo Federal da Nigéria, a proibição e restrição de uso de inseticidas pelo Governo da Nigéria e seus esforços para eliminar resíduos de inseticidas em uso são também discutidos.(AU)

Assuntos

RESUMO

The use of organochlorine pesticides (OCPs) is a worldwide public health concern given that high levels of these compounds in humans and animals can lead to serious health problems. This study aimed to evaluate the levels of 15 organochlorine pesticides in the serum of 547 blood donors in the São Paulo metropolitan region (SPMR) in 2009 and to investigate factors associated with higher levels of these compounds. The OCPs were determined by gas chromatography with micro electron capture detection. Multiple ordinal logistic regression models were employed to determine the factors associated with higher levels. Only ß-HCH and p,p'-DDE had a significant number of samples above the limit of quantification. Factors associated with higher levels of ß-HCH were age within 26 to 35 years (OR = 3.1 [1.05-9.09]), age within 36 to 45 years (OR = 18.27 [6.89-48.91]), and female gender (OR = 0.44 [0.24-0.82] for men). p,p'-DDE levels were associated with age within 26 to 35 years (OR = 2.65 [1.20-3.45]), age within 36 to 45 years (OR = 4.59 [2.64-7.92]), female gender (OR = 0.86 [0.43-0.94] for men), and previous work with pesticides (OR = 2.88 [1.22-6.84]). Lower levels of p,p'-DDE were associated with an income of 3 to 5 minimum wages (OR = 0.38 [0.19-0.75]) and with intake of foods from animal origin up to twice a week (OR = 0.15 [0.03-0.72]) and more than twice a week (OR = 0.10 [0.02-0.47]). The results of this study indicate that the study group was not exposed to high levels of OCPs.

Assuntos

RESUMO

Pesticide helps to enhance agricultural production, however, it significantly affect both socio and environmental entities of a country. In Nigeria, pesticide is widely used, thus its traces have been detected in water, soil and air. Several studies have already indicated that most of the environmental ecology (air, water, and soil) in Nigeria has been contaminated by persistent organic pesticides like organochlorine and organophosphate. Other reasons of high pesticide residues present in Nigeria environment is due to inappropriate dosage applied of pesticides that leaves behind excess. However, its residues are found above safety levels in the air, water, and soil across the nation. Based on previous analysis, it is indicated that 125,000-130,000 metric ton pesticides are being applied annually in Nigeria. Despite banned of some pesticides such as dichlorodiphenyltrichloroethane- and -Hexachlorocyclohexane, they are still being used by farmers in their agricultural production. Many of the Class 1 (high extremely toxic) pesticides are still being used in developing countries like Nigeria. Hence, there is need to sensitize and educate the general public especially the end-users (farmers) particularly on management practices of pesticides. Considering these entire hazardous situations, in this article the history of pesticide used in Nigeria has been reviewed in detail. The artic

Inseticidas ajudam a aumentar a produção agrícola, no entanto, afetam significativamente a sociedade e o ambiente do país. Na Nigéria, os inseticidas são amplamente utilizados, assim, seus resíduos foram detectados na água, solo e ar. Vários estudos já indicaram que a maior parte dos aspetos ecológicos ambientais (ar, água e solo) na Nigéria tenham sido contaminados por pesticidas orgânicos persistentes como os organoclorados (OCL) e organofosforados (OP). Outro motivo relacionado com a ocorrência de resíduos elevados de inseticidas presentes no meio ambiente na Nigéria é devido às dosagens inadequadas aplicadas de pesticidas que são aplicados em excesso. No entanto, seus resíduos são encontrados acima dos níveis de segurança no ar, água e solo em todo o país. Com base em dados anterior, é observado que 125,000-130,000 toneladas métricas de pesticidas são aplicadas por ano na Nigéria. Apesar da proibição de alguns pesticidas como o DDT (Dicloro-difenil-tricloroetano) e HCH (Hexa-cloro- ciclohexano), eles ainda estão sendo usados pelos agricultores para a produção agrícola. Muitos dos Classe 1 pesticidas (extremamente tóxicos) ainda estão sendo usados nos países em desenvolvimento como a Nigéria. Assim, não há necessidade de sensibilizar e educar o público em geral, especialmente os usuários finais (agricultores) em particular sobre as

RESUMO

Pesticide helps to enhance agricultural production, however, it significantly affect both socio and environmental entities of a country. In Nigeria, pesticide is widely used, thus its traces have been detected in water, soil and air. Several studies have already indicated that most of the environmental ecology (air, water, and soil) in Nigeria has been contaminated by persistent organic pesticides like organochlorine and organophosphate. Other reasons of high pesticide residues present in Nigeria environment is due to inappropriate dosage applied of pesticides that leaves behind excess. However, its residues are found above safety levels in the air, water, and soil across the nation. Based on previous analysis, it is indicated that 125,000-130,000 metric ton pesticides are being applied annually in Nigeria. Despite banned of some pesticides such as dichlorodiphenyltrichloroethane- and -Hexachlorocyclohexane, they are still being used by farmers in their agricultural production. Many of the Class 1 (high extremely toxic) pesticides are still being used in developing countries like Nigeria. Hence, there is need to sensitize and educate the general public especially the end-users (farmers) particularly on management practices of pesticides. Considering these entire hazardous situations, in this article the history of pesticide used in Nigeria has been reviewed in detail. The artic

Inseticidas ajudam a aumentar a produção agrícola, no entanto, afetam significativamente a sociedade e o ambiente do país. Na Nigéria, os inseticidas são amplamente utilizados, assim, seus resíduos foram detectados na água, solo e ar. Vários estudos já indicaram que a maior parte dos aspetos ecológicos ambientais (ar, água e solo) na Nigéria tenham sido contaminados por pesticidas orgânicos persistentes como os organoclorados (OCL) e organofosforados (OP). Outro motivo relacionado com a ocorrência de resíduos elevados de inseticidas presentes no meio ambiente na Nigéria é devido às dosagens inadequadas aplicadas de pesticidas que são aplicados em excesso. No entanto, seus resíduos são encontrados acima dos níveis de segurança no ar, água e solo em todo o país. Com base em dados anterior, é observado que 125,000-130,000 toneladas métricas de pesticidas são aplicadas por ano na Nigéria. Apesar da proibição de alguns pesticidas como o DDT (Dicloro-difenil-tricloroetano) e HCH (Hexa-cloro- ciclohexano), eles ainda estão sendo usados pelos agricultores para a produção agrícola. Muitos dos Classe 1 pesticidas (extremamente tóxicos) ainda estão sendo usados nos países em desenvolvimento como a Nigéria. Assim, não há necessidade de sensibilizar e educar o público em geral, especialmente os usuários finais (agricultores) em particular sobre as práticas para o manejo dos inseticidas. Con

RESUMO

Pesticide helps to enhance agricultural production, however, it significantly affect both socio and environmental entities of a country. In Nigeria, pesticide is widely used, thus its traces have been detected in water, soil and air. Several studies have already indicated that most of the environmental ecology (air, water, and soil) in Nigeria has been contaminated by persistent organic pesticides like organochlorine and organophosphate. Other reasons of high pesticide residues present in Nigeria environment is due to inappropriate dosage applied of pesticides that leaves behind excess. However, its residues are found above safety levels in the air, water, and soil across the nation. Based on previous analysis, it is indicated that 125,000-130,000 metric ton pesticides are being applied annually in Nigeria. Despite banned of some pesticides such as dichlorodiphenyltrichloroethane- and -Hexachlorocyclohexane, they are still being used by farmers in their agricultural production. Many of the Class 1 (high extremely toxic) pesticides are still being used in developing countries like Nigeria. Hence, there is need to sensitize and educate the general public especially the end-users (farmers) particularly on management practices of pesticides. Considering these entire hazardous situations, in this article the history of pesticide used in Nigeria has been reviewed in detail. The article also discussed the effects of pesticide use in Nigerianwaters, soil and on crops. The risk of residual pesticide on agricultural workers, pesticide residue riskpreventive measures by the Federal Government of Nigeria, banned and restricted pesticides in Nigeria,Nigerian Government and its efforts to eliminate persistent organic pesticides in use are also reviewedin details.

Inseticidas ajudam a aumentar a produção agrícola, no entanto, afetam significativamente a sociedade e o ambiente do país. Na Nigéria, os inseticidas são amplamente utilizados, assim, seus resíduos foram detectados na água, solo e ar. Vários estudos já indicaram que a maior parte dos aspetos ecológicos ambientais (ar, água e solo) na Nigéria tenham sido contaminados por pesticidas orgânicos persistentes como os organoclorados (OCL) e organofosforados (OP). Outro motivo relacionado com a ocorrência de resíduos elevados de inseticidas presentes no meio ambiente na Nigéria é devido às dosagens inadequadas aplicadas de pesticidas que são aplicados em excesso. No entanto, seus resíduos são encontrados acima dos níveis de segurança no ar, água e solo em todo o país. Com base em dados anterior, é observado que 125,000-130,000 toneladas métricas de pesticidas são aplicadas por ano na Nigéria. Apesar da proibição de alguns pesticidas como o DDT (Dicloro-difenil-tricloroetano) e HCH (Hexa-cloro- ciclohexano), eles ainda estão sendo usados pelos agricultores para a produção agrícola. Muitos dos Classe 1 pesticidas (extremamente tóxicos) ainda estão sendo usados nos países em desenvolvimento como a Nigéria. Assim, não há necessidade de sensibilizar e educar o público em geral, especialmente os usuários finais (agricultores) em particular sobre as práticas para o manejo dos inseticidas. Considerando estas situações de perigo real, neste artigo o histórico de uso de inseitidas naNigéria foi estudo em detalhe. O artigo também discute os efeitos da utilização de inseticidas nas águas,no solo e nas culturas. O risco de contaminação para os trabalhadores rurais as medidas preventivaspara controlar risco de resíduos adotadas pelo Governo Federal da Nigéria, a proibição e restrição de uso de inseticidas pelo Governo da Nigéria e seus esforços para eliminar resíduos de inseticidas em uso são também discutidos.

Assuntos

RESUMO

The organochlorine insecticide γ-hexachlorocyclohexane (γ-HCH, lindane) and its non-insecticidal α- and ß-isomers continue to pose serious environmental and health concerns, although their use has been restricted or completely banned for decades. In this study we report the first evidence of the growth ability of a Streptomyces strain in a mineral salt medium containing high doses of α- and ß-HCH (16.6 mg l(-1)) as a carbon source. Degradation of HCH isomers by Streptomyces sp. M7 was investigated after 1, 4, and 7 days of incubation, determining chloride ion release, and residues in the supernatants by GC with µECD detection. The results show that both the α- and ß-HCH isomers were effectively metabolized by Streptomyces sp. M7, with 80 and 78 % degradation respectively, after 7 days of incubation. Moreover, pentachlorocyclohexenes and tetrachlorocyclohexenes were detected as metabolites. In addition, the formation of possible persistent compounds such as chlorobenzenes and chlorophenols were studied by GC-MS, while no phenolic compounds were detected. In conclusion, we have demonstrated for the first time that Streptomyces sp. M7 can degrade α- and ß-isomers individually or combined with γ-HCH and could be considered as a potential agent for bioremediation of environments contaminated by organochlorine isomers.

Assuntos

RESUMO

The levels of organochlorine pesticide residues FONT FACE=Symbol>¾ /FONT> hexaclorobenzene (HCB), lindane (gamma-HCH), aldrin and 4,4'dichloro diphenil 1,1'dichloroethylene (p,p'-DDE) - present in mammary adipose tissue samples from women living in Cordoba (Spain) were evaluated. The compound found at the highest concentration was p,p´-DDE (1.869(mug/g of adipose tissue), which was present in 100% of the analyzed samples. The average levels of HCB, gamma-HCH and aldrin were 0.236, 0.003 and 0.006mug/g of adipose tissue, respectively. The tissue levels of organochlorine residues were correlated with the weekly intake of meat and fish by donors. Only the tissue levels of p-p´-DDE were significantly (p FONT FACE=Symbol>£ /FONT>0.05) affected by the frequency of meat intake. Donors with a meat intake higher than four times a week presented an average level of 2.833mug/g of adipose tissue.

Níveis de resíduos dos pesticidas organoclorados, hexaclorobenzeno (HCB), lindano gama-HCH), aldrin e 4,4'-diclorodifenil-1,1'dicloroetileno (p,p'-DDE) foram determinados em tecido adiposo mamário de mulheres residentes em Córdoba, Espanha. A maior concentração média foi detectada para o p,p'-DDE (1,869 mig/g de tecido adiposo), que estava presente em 100% das amostras. As concentrações médias de HCB, gama-HCH e aldrin encontrados foram 0,236, 0,003 e 0,006mig/g de tecido adiposo, respectivamente. Os níveis dos resíduos detectados nas amostras foram relacionados ao consumo semanal de carne e pescado pelas doadoras. O único composto cujos níveis variaram significativamente (p FONT FACE=Symbol>£ /FONT>0,05) em função da freqüência de consumo de carne foi o p,p'-DDE, tendo apresentado concentração média de 2,833 mig/g de tecido adiposo quando as doadoras relataram uma freqüência de consumo de carne superior a quatro vezes por semana.

RESUMO

The levels of organochlorine pesticide residues FONT FACE=Symbol>¾ /FONT> hexaclorobenzene (HCB), lindane (gamma-HCH), aldrin and 4,4'dichloro diphenil 1,1'dichloroethylene (p,p'-DDE) - present in mammary adipose tissue samples from women living in Cordoba (Spain) were evaluated. The compound found at the highest concentration was p,p´-DDE (1.869(mug/g of adipose tissue), which was present in 100% of the analyzed samples. The average levels of HCB, gamma-HCH and aldrin were 0.236, 0.003 and 0.006mug/g of adipose tissue, respectively. The tissue levels of organochlorine residues were correlated with the weekly intake of meat and fish by donors. Only the tissue levels of p-p´-DDE were significantly (p FONT FACE=Symbol>£ /FONT>0.05) affected by the frequency of meat intake. Donors with a meat intake higher than four times a week presented an average level of 2.833mug/g of adipose tissue.

Níveis de resíduos dos pesticidas organoclorados, hexaclorobenzeno (HCB), lindano gama-HCH), aldrin e 4,4'-diclorodifenil-1,1'dicloroetileno (p,p'-DDE) foram determinados em tecido adiposo mamário de mulheres residentes em Córdoba, Espanha. A maior concentração média foi detectada para o p,p'-DDE (1,869 mig/g de tecido adiposo), que estava presente em 100% das amostras. As concentrações médias de HCB, gama-HCH e aldrin encontrados foram 0,236, 0,003 e 0,006mig/g de tecido adiposo, respectivamente. Os níveis dos resíduos detectados nas amostras foram relacionados ao consumo semanal de carne e pescado pelas doadoras. O único composto cujos níveis variaram significativamente (p FONT FACE=Symbol>£ /FONT>0,05) em função da freqüência de consumo de carne foi o p,p'-DDE, tendo apresentado concentração média de 2,833 mig/g de tecido adiposo quando as doadoras relataram uma freqüência de consumo de carne superior a quatro vezes por semana.