Home > Application of Biochar in Reducing the Levels of Pesticide Residues in Contaminated Soils and Food Crops: A Strategy to Minimize the Health Risk
Application of Biochar in Reducing the Levels of Pesticide Residues in Contaminated Soils and Food Crops: A Strategy to Minimize the Health Risk
Organochloride pesticides (OCPs) also known as ―endocrine disrupting‖ chemicals are one of the persistent group of contaminants in soil that has gained worldwide concerns over the past few decades. They can transferred into the vegetables grown on the contaminated soils and eventually entered the food chain. The associated risk to human health makes the remediation of pesticide-contaminated soil a crucial undertaking. This research work is divided into different parts and several experiments were conducted to achieve the proposed objectives. The first study was carried out to evaluate the concentrations of OCPs in soils and vegetables grown in selected sites of Khyber Pakhtunkhwa (KP), Pakistan. The soil and selected vegetable species including Spinacia oleracea, Raphanus sativus, Brassica rapa, Lactuca sativa, Allium cepa and Allium sativum were collected from six districts (Peshawar, Charsadda, Nowshera, Mardan, Swabi and Swat), and were analysed for selected OCPs. Results showed that the concentrations of the selected OCPs exceeded their respective maximum residue limits (MRLs) in most of the soil samples and showed great variation from site to site. In case of the studied vegetables, the most contaminated observed was Lactuca sativa (28.9 μg kg-1), followed by Raphanus sativus (26.6 μg kg-1), Spinacia oleracea (25.8 μg kg-1), Allium cepa (16.3 μg kg-1), Brassica rapa (15.6 μg kg-1), and Allium sativum (14.7 μg kg-1). Analysis of health risk revealed that incremental lifetime cancer risks (ILCR) associated with dietary exposure of Σ30OCP through vegetables consumption by adults and children were below the acceptable risk level (10-6), indicating no cancer risk to the consumers. Moreover, exposure to the endocrine disruptor and probable carcinogen heptachlor epoxide (in children only) contributes toward non-cancer risk (HQ>1) from ingestion of selected vegetables. The presence of the banned OCPs in soils and vegetables in xvi the study area indicates that these legacy chemicals are still being used illegally for agricultural purposes which may be a cause for concern. Similarly, the second study was focused on the remediation of OCP-contaminated soils, as most of the OCPs are known to be possible/suspected endocrine disruptors and carcinogenic in nature and may severely affect humans or other living biota. Therefore, a 65-d incubation experiment was conducted to investigate the efficacy of biochars on the accessibility of OCPs, and also to evaluate their influence on soil microbial community. Results indicated that despite greater persistence of OCPs in soil, the application of selected biochars significantly (p<0.01) reduced the accessibility of åOCPs in contaminated soil as compared to the control soil during 65-days incubation period. Moreover, the findings from total phospholipid acid (PLFA) and Illumina next-generation sequencing revealed that the incorporation of biochar have altered the soil microbial community structure over time. Higher abundances of Proteobacteria, Firmicutes, Gemmatimonadetes, and Actinobacteria, were found in the biochar amendments. This recommends that biochar amendment (3%) could be advantageous for sustaining soil microbial communities and may thus likely influence the eco-toxicological processes and potential accumulation of OCPs. The third study was conducted to evaluate the effects of biochar (BC), biochar-based organic fertilizer (OF) and their combination (BCOF) on the bioaccessibility and accumulation of endocrine disruptive pesticides (EDPs) into leafy vegetables (Lactuca sativa and Spinacia oleracea) grown in a contaminated soil. The results revealed that application of BCOF and OF significantly (p<0.05) decreased bioaccessible concentrations of åEDPs in leafy vegetables by 23 and 44%, respectively, BC was particularly effective and decreased åEDPs bio-accessible concentrations by 60%, as compared to control. Biomass production, however, xvii increased the most for the BCOF amendments, (with a 70% increase in crop production compared to the control soil). Moreover, the incremental lifetime cancer risk (ILCR) values for selected EDPs were significantly (p<0.01) reduced in the amended soil as compared to control. These findings suggest that OF, BCOF and BC could be useful soil amendments to minimize the EDPs bioaccessibility in a degraded soil and their subsequent exposure to humans through vegetable consumption. Likewise, to investigate the effects of different biochars on the bioaccessible fractions of OCPs in a contaminated soil and their subsequent bioaccumulation into vegetable crops a fourth study was conducted. Four different biochars, derived from sewage sludge, soybean straw, rice straw and peanut shells were applied to a pesticide-contaminated soil at 2%, and the resulting impacts were measured. The results indicated that following biochar additions, the bioaccessible fractions of OCPs in soil and their accumulation in vegetable crops significantly (p<0.01) reduced, as compared to control. Risk assessment showed that biochar amendments markedly (p<0.01) decreased the hazard quotient (HQ) indices and the incremental lifetime cancer (ILCR) values for OCPs associated with the consumption of vegetable crops. From the results of the present studies it is concluded that the application of biochar could play a promising role in enhancing microbial abundance, reducing accessibility, restricting bioaccumulation of organochlorine pesticides in vegetables and decreasing their associated human health risk.
صلوۃ التر اویح اور جسم انسانی اللہ تعالیٰ نے انسان کو اشرف المخلوقات بنایا اور عظمت کا تاج اس کے سر پر سجایا۔ اس کو انبیاء کرام کے توسل سے آگاہ فرمایا کہ ہدایت کا راستہ کونسا ہے اور گمراہی اور ذلت کا راستہ کون سا ہے، اس کو اس کی پیدائش کی غرض و غایت سے بھی خبر دار کیا کہ تمہاری پیدائش کا مقصد میری عبادت اور معرفت ہے۔ جو شخص زندگی بھر اللہ کی عبادت اور بندگی کرتارہا وہ کامیاب و کامران رہا اور جس نے اس کی عبادت سے منہ موڑ اخائب وخاسر ہوا۔ دیگر عبادات کی طرح صلوۃ التراویح بھی ایک اہم عبادت ہے۔ اس کی ادائیگی سے اس کو ڈھیروں نیکیوں کا خزانہ میسر آتا ہے وہاں یہ عبادت اپنے عبادت گزار کے جسم و جان کے لیے بھی انتہائی نافع ہے۔ جملہ عبادات کا بنظر غائر جائزہ لیا جائے تو اس سے یہ بات مترشحّ ہو جاتی ہے کہ احکام الٰہی کی پیروی سے جہاں روحانی آسودگی کا سامان میسر آتاہے وہاں جسمانی اعضاء کی صحت بھی برقرار رہتی ہے۔ نماز کی ترتیب بھی حکمت سے خالی نہیں ہے۔ فجر کی نماز مختصر ہوتی ہے اور صرف چار رکعت کی ادائیگی سے مسلمان اپنے فرض سے عہدہ برآ ہو جا تا ہے۔ اور اس میں جوحکمت کارفرما ہے وہ یہ ہے کہ انسان کے جسم میں موجود معدہ خالی ہوتا ہے اور اس مختصرسی عبادت کی ادائیگی سے جسم انسانی میں کوئی گراوٹ محسوس نہیں ہوتی اور طبیعت سرور و نشاط محسوس کرتی ہے۔ دو پہر ظہر کی نماز میں 12 رکعت اس لیے رکھ دی گئی ہیں کہ انسان دوپہر کو کھانا کھا کر عبادت کے لیے حاضر ہو جاتا ہے۔ اور تعداد میں اضافہ کے سبب اس کے معدہ کی حرکات وسکنات میں بھی زیادتی آجاتی ہے...
Islamic Studies as a discipline in Nigerian Universities was introduced to provide training and the dissemination and promotion of Knowledge of Islam in particular and Islamic culture in general. The discipline is designed to pursue the development of Muslims through inculcation of Islamic values, norms and principles, without which the goal of ideological, moral, intellectual and economic development of any Muslim Nation may not be achieved. The programme seeks to make students appreciate the Qur’an and Hadith of the Prophet (S.A.W) as the two fountain heads on which Islam is based. The curriculum is structured to produce qualified intellectuals, professionals and scholars by integrating the articles of faith (Iman), qualities of knowledge, (Ilm) and good character (Akhlaq) to serve as agents of comprehensive, balanced and sustainable development. It focuses on developing practical solutions through research on contemporary problems of Nigerian Muslim society in particular and the Muslim world in general. This paper is going to discuss on the teaching methodologies for Islamic studies in the Nigerian Universities. A suitable teaching method is very important in helping to achieve desired objectives and behavioral outcome expected on the learners. The research Methodology to be adopted in conducting this research is analytical methods by studying facts and information on research methodologies used for teaching Islamic studies in Nigerian Universities and analyses them to make a critical evaluation.
Textile dyes have always been considered in the context of recalcitrant xenobiotics compounds in water and soil ecology. Present research work was focused on the bioremediation potential of Agaricus species to decolorize and to detoxify the different synthetic dyes and dye containing effluents. The purification, characterization, kinetics & thermodynamic studies of ligninolytic enzymes produced by the fungi during dye decolorization process, were also performed. Complete (100%) removal of NOVASOL Direct Black and 83.34 % Reactive Black by Agaricus bitorqus A66 & Agaricus bisporus A21 were attained by optimizing optimal conditions like media composition, pH, temperature, inoculum size, carbon and nitrogen supplements, metal ions, redox mediators and dye concentration. In the entire processes of optimization of decolorization lignin peroxidase (LiP) was the major enzyme with minor activities of MnP and laccase when the decolorization of Novasol black was carried out by Agaricus bitorqus A66 and manganese peroxidase (MnP) was the main enzyme with minor LiP and laccase activities in case of reactive black treated by Agaricus bisporus A21. As highly efficient decolorization (100%) of synthetic dye was attained by these Agaricus species in a reasonably short period of time under optimum conditions, these were therefore, applied to check out their potential application in the decolorization of different practical/real textile industry effluent. It was observed that complete (100%) and 95.66 % decolorization of Navy blue colored effluent was achieved by Agaricus bitorqus and Agaricus bisporus A21 , respectively under optimum conditions. To access the water quality parameters, the treated and untreated effluent samples were analyzed to determine COD, BOD, TSS and TDS. The fungal treated effluents were less polluted as compared to original industrial effluents. The enzymes (LiP & MnP) produced under optimum decolorization conditions were purified to 1.54 & 6.9 fold with % yield of 6.74 and 8.48, respectively by ammonium sulfate precipitation, followed by three purification steps including, Dialysis, gel-filtration and anion- exchange chromatography. MnP and LiP secreted by respective fungi displayed optimum activities pH 7.0 & 6.0 and at 45 &400C, respectively. The Km values for veratryl alcohol and MnSO4 were 16.67 mM, 3.33 mM for MnP and LiP, having Vmax values of 179.17 and 231.00 mM, respectively. Thermodynamic and activation parameters provide a detailed mechanism for many chemical and biological reactions. The kinetic and thermodynamic characterization revealed Gibbs free energy ΔG* values for denaturation of MnP and LiP as 272.12 & 272.6 KJmol-1, enthalpy of thermal unfolding ΔH* of transition state was 39.91& 72.83 KJmol-1 and entropy of thermal unfolding (ΔS*) was -707.94 &, -609 Jmol-1K-1 at 50oC along with activation energy for inactivation of Ea 42.6, 75.6 KJmol-1, respectively.