Abstract
The control of drinking water quality is critical in preventing fluorosis. In this study humic substances (HS) are considered as representative of natural organic matter (NOM) in water. We show that when HS aggregate the response of fluoride ion selective electrodes (ISE) may be perturbed. Dynamic light scattering (DLS) results of both synthetic solutions and natural water sample suggest that low pH and high ionic strength induce HS aggregation. In the presence of HS aggregates, fluoride concentration measured by ISE has a reduction up to 19%. A new "open cage" concept has been developed to explain this reversible phenomenon. The interference of HS aggregation on fluoride measurement can be effectively removed by centrifugation pretreatment.
| Original language | English |
|---|---|
| Pages (from-to) | 66-71 |
| Number of pages | 6 |
| Journal | Chemosphere |
| Volume | 159 |
| Early online date | 6 Jun 2016 |
| DOIs | |
| Publication status | Published - 1 Sept 2016 |
Funding
The authors would like to acknowledge: Stephen McClatchey and Nadege Ferlinare (ENU) for their assistance with DLS and other analytical protocols; Koenraad Collart and Srinivas Popuri (HWU) for conducting elementary and ash analysis, respectively; Godfrey Mkongo (Ngurdoto Defluoridation Research Station, Tanzania) for collecting the natural water in the field; and David McMullan (Scottish Water) for carrying out water analysis. Professor Thomas J. Manning (Valdosta State University, USA) is thanked for valuable comments on territorial binding. The PhD studentship for Junjie Shen was provided by Energy Technology Partnership (ETP) Scholarship with Drinking Water Quality Regulator for Scotland (DWQR) as the industrial sponsor. Appendix A
Keywords
- Dynamic light scattering (DLS)
- Fluoride
- Humic substances
- Ion selective electrode (ISE)
ASJC Scopus subject areas
- General Chemistry
- Environmental Chemistry