Analysis of toxicity from the effluent generated in a furniture industry spray booth using the species Lactuca sativa and Allium cepa

Abstract This study evaluated the toxicity of effluent generated in a furniture industry spray booth, before and after treatment in a system composed of an anaerobic sequencing batch (ASBR) followed by an aerobic sequencing batch reactor (SBR). The toxicity tests were carried out with raw (with and without dilutions) and treated effluent to evaluate the toxic potential using Allium cepa and Lactuca sativa as bioindicators. The toxicity tests, using Allium cepa and Lactuca sativa, indicated that the anaerobic-aerobic treatment performed was efficient to reduce the toxicity of the paint booth effluent. The raw effluent, undiluted and diluted (at 1:10; 1:8 and 1:6 dilutions), showed toxic effect on the root growth of Allium cepa, as it inhibited root growth by 100%. In the tests with Lactuca sativa seeds, there was partial inhibition, between 44% and 63%, for 1:10 and 1:8 dilutions, but for the 1: 6 dilution and without dilution of effluent the inhibition was 100%. The treated effluent, in an ASBR followed by an SBR, presented a small percentage of inhibition for tests with Allium cepa (13%) and Lactuca sativa seeds (4%). The effluent treated by the anaerobic system followed by aerobic presented low toxicity without generating lethal or sub-lethal effects to the test organisms, which indicates the efficiency of the treatment process.

摘要 本研究评估了某家具行业喷漆房产生的废水在经厌氧序批式反应器（anaerobic sequencing batch reactor, ASBR）-好氧序批式反应器（aerobic sequencing batch reactor, SBR）组合系统处理前后的毒性。本研究以洋葱（Allium cepa）和生菜（Lactuca sativa）为生物指示物，采用未稀释及不同稀释比例的原废水与处理后废水开展毒性试验，以评估其潜在毒性。以洋葱和生菜为受试生物的毒性试验结果显示，本研究所采用的厌氧-好氧组合处理工艺可有效降低喷漆房废水的毒性。未稀释及1:10、1:8、1:6稀释的原废水对洋葱根生长均表现出完全抑制效应，根生长抑制率达100%。在生菜种子试验中，1:10和1:8稀释组的根生长抑制率介于44%~63%，但1:6稀释组及未稀释原废水组的抑制率均为100%。经ASBR-SBR组合系统处理后的废水，对洋葱根生长及生菜种子发芽的抑制率仅分别为13%和4%。该厌氧-好氧组合工艺处理后的废水毒性极低，未对受试生物产生致死或亚致死效应，证实了该处理工艺的有效性。