Data on fluoride concentration and health risk assessment of drinking water in Khorasan Razavi province, Iran

While fluoride (F) is an essential anion to keep the human body healthy, high F intake could lead to serious health problems. The monitoring of F in drinking water as the main route of F intake, is a key factor in preventing its negative health consequences. Here, we present the F levels in drinking water distribution networks of Khorasan Razavi province in Iran which collected during 2016–2017. The non-cancer human risk attributed to F in municipal and rural regions, also, estimated by calculating the chronic daily intake (CDI) and hazard quotient (HQ) for adults and children. Samples taken from drinking water distribution network in 112 different locations across the Khorasan Razavi and the F concentration determined using standard SPADNS Method. Having a minimum of 0.09 and 0.16 and a maximum of 1.7 and 1.1 mg L−1, the mean F level in municipal and rural samples were 0.74 and 0.59 mg L−1, respectively. The mean CDI values for F in municipal samples were 1.3×10−2, 3.34×10−4, and 8.56×10−6 mg kg−1day−1, for men, women, and children, respectively. The CDI for rural samples were 1.51×10−2, 3.88×10−4, and 9.96×10−6 mg kg−1day−1, for men, women, and children, respectively. The mean HQ of F for men, women, and children in municipal and rural samples were 2.17×10−1, 5.56×10−3, and 1.43×10−4, and 2.44×10−1, 6.26×10−3 and 1.61×10−4, respectively. Locations with a HQ>1, needs appropriate strategies for reducing the F level in drinking water to prevent the potential health risks.

for men, women, and children, respectively. The mean HQ of F for men, women, and children in municipal and rural samples were 2.17×10 −1 , 5.56×10 −3 , and 1.43×10 −4 , and 2.44×10 −1 , 6.26×10 −3 and 1.61×10 −4 , respectively. Locations with a HQ41, needs appropriate strategies for reducing the F level in drinking water to prevent the potential health risks.
& 2018 Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Subject area
Water quality assessment More specific subject area Drinking water monitoring and quality Type of data Table, figure How data was acquired The fluoride level in samples determined according to the standard methods for the examination of water and wastewater (SPADNS Method) using a DR-5000 spectrophotometer (UV-vis).

Data format
Raw, analyzed

Experimental factors
According to the study area, 112 sampling points were identified. After sampling, all samples were stored and carried to the laboratory analyzed for the concentration of fluoride.

Experimental features
Measuring the concentration of fluoride ion in the samples of drinking water Data source location Mashhad city, Khorasan Razavi province, east of Iran Data accessibility Data are included in this article and supplemented excel file

Value of the data
The unusual properties of fluoride (F) in having detrimental health effects at excess or deficient intake levels, give these data value to be available.
Drinking water is the main route of fluoride intake. The role of F in keeping bones and teeth healthy is fully understood. Harmful non-carcinogenic problems related to excess F intake are skeletal fluorosis, dental fluorosis, and dental caries.
The estimation of non-cancer human health risk assessment attributed to F for the population who consume the water, is a systematic approach for developing management strategies for supply safe drinking water.

Data
The fluoride (F) data in this report obtained from the monitoring of the drinking water distribution networks of Khorasan Razavi province during 2016-2017. Samples taken from 112 different locations and analyzed for the F concentration by the DR-5000 spectrophotometer, according to the standard methods for the examination of water and wastewater (SPADNS Method) [1]. The study area is shown in Fig. 1. Tables 2 and 3 show the F levels in the drinking water supplies of municipal and rural areas, respectively.

Experimental design, materials, and methods
Fluoride (F) is a critical ion in drinking water. The unusual nature of F in posing detrimental health effects at excess or deficient intake, motivated researchers to conduct numerous studies on both F level in drinking waters and excessive F removal from contaminated streams [2][3][4][5].
Human health risk assessment for water contaminants estimate the nature and probability of adverse health effects for the population who receive the chemicals from drinking water. It provides a systematic approach for developing management strategies to supply safe drinking water. The data obtained from the analysis of samples for F in 112 locations across the Khorasan Razavi province undergo a health risk assessment for non-cancer effects. The following equation (Eq. 1) was used to calculate the non-carcinogenic health risk [6,7]: where HQ is non-carcinogenic risk quotient. CDI and RfD are chronic daily intake (mg kg −1 day −1 ) and reference dose (mg kg −1 day −1 ), respectively. The intake reference dose for F is 0.06 mg kg −1 day −1 [8].
The following Eq. (2) is used to calculate the CDI: where C W , W I , F, D, W, and T are F content in drinking water (as measured), water intake, exposure frequency, exposure duration, body weight, and average life time, respectively [4]. The constants used for the above formula are shown in Table 1. An HQ value more than one will show a substantial risk, where the higher the value, the greater the likelihood of adverse non-carcinogenic health effects. The RfD value for F − was 0.6 mg kg −1 day −1 . The mean F concentration for municipal and rural samples were 0.74 and 0.59 mg L −1 , respectively. The concentration of F in municipal and rural samples was 1.7 to 0.09 mg L −1 and 1.3 to 0.16 mg L −1 , respectively. Based on the analyzed data, the mean value of the CDI for F in municipal samples for men, women, and children was 1.