Water quality assessment using a portable UV optical absorbance nitrate sensor with a scintillator and smartphone camera

Water quality assessment using a portable UV optical absorbance nitrate sensor with a scintillator and smartphone camera

Nitrate contamination of water sources is a global environmental concern. A major source of pollution is agricultural runo,f which can contain decomposed organic matter, fertilizer, and animal or human waste. Nitrate adversely afects the stability of water systems such as dams and rivers and thus al...

Full description

Saved in:
Bibliographic Details
Published in:Water S. A. Vol. 47; no. 1; pp. 135 - 140
Main Authors: Ingles, JMDFP, Louw, T.M, Booysen, M.J
Format: Journal Article
Language:English
Published: Gezina Water Research Commission (WRC) 01-01-2021
Water Research Commission
Subjects:
Absorbance
Absorption coefficient
Absorptivity
Agricultural runoff
Analysis
Bandpass filters
Cameras
Chemical analysis
Contamination
Cost analysis
Dam stability
Developing country
Dilution
Environmental perception
Fertilizers
Human wastes
Laboratories
Laws, regulations and rules
Measuring instruments
Nitrates
Optical properties
Optics
Organic matter
Pollution sources
Public health
Quality assessment
Quality control
Rivers
Runoff
Scintillation counters
Sensors
Smart phones
Smartphones
Spectrophotometers
spectroscopic analysis
Spectrum analysis
UV absorbance analysis
Water analysis
Water pollution
Water quality
Water quality assessments
Water sampling
South Africa
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Nitrate contamination of water sources is a global environmental concern. A major source of pollution is agricultural runo,f which can contain decomposed organic matter, fertilizer, and animal or human waste. Nitrate adversely afects the stability of water systems such as dams and rivers and thus also public health. Regulation is essential but dificult to implement, given that measuring nitrates is laborious, and normally done using chemical assays in laboratories. We present a novel portable nitrate sensor that uses a smartphone camera fitted with low-cost optics. The sensor uses ultraviolet absorbance analysis to detect nitrates in water samples and quantify the concentration. The sensor's absorptivity when a bandpass filter was used was 0.0681 L∙mg−1∙cm−1 compared to 0.0934 L∙mg−1∙cm−1 measured with a spectrophotometer in a laboratory. Measurements by the sensor of the concentration of nitrates in two environmental samples difered from those taken by the spectrophotometer by 19% and 7%. The sensor achieved a nitrate concentration measurement resolution of 0.2 mg∙L−1, and a detection range of 0-5 mg∙L−1, with higher concentrations requiring dilution to quantify. Our tests showed that the smartphone-based nitrate sensor is suficiently accurate to be used as an inexpensive instrument for nitrate analysis in the field.
ISSN:0378-4738
1816-7950
DOI:10.17159/wsa/2021.v47.i1.9453