Depleting aquifers, lack of planning and low socioeconomic status of Pakistani farmers have led them to use wastewater (WW) for irrigating their crops causing food contamination with heavy metals and ultimately negative effects on human health. This study evaluates the effects of chitosan (CH) and biochar (BC) on growth and nutritional quality of brinjal plant together with in situ immobilization of heavy metals in a soil polluted with heavy metals due to irrigation with wastewater (SPHIW) and further irrigated with the same WW. Both CH and BC were applied at three different rates i.e. low rate [(LR), BC0.5%, CH0.5% and BC0.25%+CH0.25%], medium rate [(MR), BC1%, CH1% and BC0.5%+CH0.5%] and high rate [(HR), BC1.5%, CH1.5% and BC0.75%+CH0.75%]. Result revealed that brinjal growth, antioxidant enzymes, and fruit nutritional quality significantly improved from LR to HR for each amendment, relative to control. However, these results were more prominent with BC alone and BC+CH, compared with CH alone at each rate. Similarly, with few exceptions, significant reduction in Ni, Cd, Co, Cr and Pb concentrations in the root, shoot and fruit were found in sole CH treatment both at LR and MR but in both CH and BC+CH treatments at HR, relative to control. Interestingly, the concentrations of Fe in the roots, shoots and fruit were more pronounced at BC treatments relative to CH and BC+CH treatments at each rate, compared to control. Overall, the BC+CH treatment at HR was the most effective treatment for in situ immobilization of heavy metals in SPHIW and further irrigated with the same WW, compared to rest of the treatments. This study indicates that BC0.75%+CH0.75% treatment can be used to reduce mobility and bioavailability of heavy metals in SPHIW and facilitates plant growth by improving the antioxidant system. However, the feasibility of BC0.75%+CH0.75% treatment should also be tested at the field scale.

含水层的枯竭，缺乏规划和巴基斯坦农民的社会经济地位低下，导致他们使用废水（WW）灌溉作物，从而导致食物被重金属污染，最终对人类健康造成负面影响。这项研究评估了壳聚糖（CH）和生物炭（BC）对茄子植物生长和营养质量的影响以及在废水灌溉（SPHIW）导致的重金属污染土壤中原位固定化重金属并进一步灌溉相同的WW。CH和BC均以三种不同的比例施用，即低比例[（LR），BC0.5％，CH0.5％和BC0.25％+ CH0.25％]，中等比例[（MR），BC1％，CH1 ％和BC0.5％+ CH0.5％]和​​高比率[（HR），BC1.5％，CH1.5％和BC0.75％+ CH0.75％]。结果显示茄子生长，抗氧化酶，相对于对照，每次修正从LR到HR的水果营养质量均得到显着改善。但是，与单独使用CH的每个比率相比，单独使用BC和BC + CH的结果更为突出。同样，除少数例外，在LR和MR的单独CH处理中，根，枝和果实中的Ni，Cd，Co，Cr和Pb浓度显着降低，而在HR的CH和BC + CH处理中，相对控制。有趣的是，与CH和BC + CH处理相比，与对照相比，BC处理相对于CH和BC + CH处理，根，茎和果实中Fe的浓度更为显着。总体而言，与其余的治疗相比，HR的BC + CH处理是将SPHIW中的重金属原位固定并用相同的WW进一步灌溉的最有效的治疗方法。这项研究表明BC0。75％+ CH0.75％的处理可用于降低SPHIW中重金属的迁移率和生物利用度，并通过改善抗氧化剂系统促进植物生长。但是，BC0.75％+ CH0.75％处理的可行性也应在现场进行测试。