Accurate
and rapid detection of toxicity in water bodies is critical
for environmental monitoring, especially during environmental emergencies.
Currently, smartphone-based sensors capable of detecting toxicity
in colored water samples. This paper introduces the smartphone-assisted
three-dimensional (3D)-printed acute toxicity detector (sATD), a novel
device designed to quickly measure the inhibition rate on luminescent
bacteria, thereby providing an efficient and affordable means for
on-site acute toxicity assessment. To ensure stable image acquisition,
the entire device is enclosed in a 3D-printed, sealed black box. Three
different brands of smartphones were examined for the best performance.
The sATD-IR (smartphone-assisted 3D-printed acute toxicity detector
- inhibition rate) offers a straightforward and precise method for
on-site luminescence inhibition detection, facilitating monitoring
of acute toxicity in regional water. The sATD-IR system was validated
by using a variety of samples. For example, the half-maximal inhibitory
concentration (IC50) value for the heavy metal Zn2+ using the sATD-IR system was 1.727 mg/L, which is very close to
the IC50 value of 1.656 mg/L obtained using the standard
method. More importantly, our investigation examined how color can
affect sample toxicity detection. A correction algorithm based on
RGB analysis to accurately determine the inhibition rate for colored
samples was proposed and validated.