This paper presents an application of continuous monitoring of the emission and uptake rate of CO₂ in Lemna toxicity test. On a real-time basis, the CO₂ concentration data were collected by the Arduino platform-based respiratory activity measuring system (ResTox) and reported as CO₂ concentration dynamic curves. The results of CO₂ measurements demonstrated that tested metals (Co, Cu, Hg, and Cd), as well as herbicides (nicosulfuron, diquat, and tembotrione), stimulated the CO₂ exchange rates at low doses, while at high doses CO₂ exchange rates were inhibited. The addition of higher concentrations of clopyralid stimulated photosynthetic activity and caused a higher increase in respiration rates indicating its mode of action as auxin mimic herbicide. The results obtained underline the necessity of considering other biological endpoints like continuous measurements of gas exchange from the very beginning of exposure to toxicants. Simultaneous measurements of real-time CO₂ concentrations, as the primary effect of toxicant mode of action, and processes that are supported by carbon flux, as the secondary effect or endpoint, are needed to relate actual and substrate-induced or inhibited respiration and photosynthesis to those processes. Therefore, continuous measurements of CO₂ exchange rates can be implemented for the initial screening of potential toxicity to give valuable information that is needed for further examination of toxicity mechanisms and risk assessment.

本文介绍了连续监测CO ₂排放和吸收率在Lemna毒性试验中的应用。实时地，基于Arduino平台的呼吸活动测量系统（ResTox）收集了CO ₂浓度数据，并报告为CO ₂浓度动态曲线。CO的结果₂的测量表明，测试的金属（钴，铜，汞，和Cd），以及除草剂（烟嘧磺隆，敌草快，和特波三酮），刺激了CO ₂在低剂量的汇率，而在高剂量CO ₂汇率受到抑制。较高浓度的氯吡格雷可刺激光合作用，并导致呼吸频率增加，表明其作为生长素模拟除草剂的作用方式。获得的结果强调必须考虑其他生物学终点，例如从接触毒物开始就连续测量气体交换。需要同时测量实时CO ₂浓度（作为有毒物质作用模式的主要作用）以及由碳通量支持的过程（作为次要作用或终点），以关联实际的和底物诱导的或抑制的呼吸作用和光合作用那些过程。因此，连续测量CO ₂ 可以对潜在的毒性进行初步筛选时使用汇率，以提供进一步检查毒性机制和风险评估所需的有价值的信息。