Supporting Information
Phthalate esters and organochlorine pesticides in agricultural soils and vegetables from fast-growing regions: A case study from eastern China
Jianteng Sun1,2, Lili Pan1, Daniel C.W. Tsang2, Zhiheng Li1, Lizhong Zhu1,*, Xiangdong Li2,*
1 Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
2 Department of Civil and Environmental Engineering,The Hong Kong Polytechnic University, Hung Hom, Kowloon,Hong Kong
* Corresponding author.
Tel.: 86-57188273733; Fax:86-57188273733; E-mail: (L. Z. Zhu)
Tel.:852-27666041; Fax:852-23346389; E-mail: (X. D. Li)
Contents
Text SI-1. Health risk assessments.
Table SI-1. Parameters for adults and children in the exposure risk assessment.
Table SI-2. Parameters in the exposure risk assessment.
Table SI-3. Location information of the sampling areas.
Text SI-1. Health risk assessments
The exposure noncarcinogenic and carcinogenic risks of selected contaminants in the soils to human health were estimated using the methods recommended by the USEPA (1997). The average daily dose (ADD, mg·kg-1·day-1) via non-dietary (i.e., soil ingestion, inhalation and dermal contact) and dietary (intake of agricultural products) exposure routes were estimated as follows.
(1)
(2)
(3)
(4)
where ADD (mg·kg-1·day-1) is the average daily dose via non-dietary, including soil ingestion (ADDingest), inhalation (ADDinhale), and dermal contact (ADDdermal), as well as dietary (ADDintake). Csoil is the concentration of the pollutant in the soil (mg·kg-1); IRS is the soil ingestion rate (mg·day-1); EF is the exposure frequency (days·yr-1); ED is the exposure duration (years); BW is the body weight (kg); AT is the average lifetime exposure (days); IhR is the inhalation rate (m3·day-1); PEF is the particulate emission factor (m3·kg-1); SA is the dermal surface area (cm2·day-1); AF is the soil adherence factor (mg·cm-2); ABS is the fraction absorbed dermally from the soil (unitless); BAF is the bioaccumulation factor from soil to agricultural products (vegetable); IRF is the daily intake rate of the agricultural products (mg·day-1) by local residents (IRF for children is set to 1/3 of that for adults). CF is the conversion factor (kg·mg-1)
Hazard quotient (HQ) was used to estimate the noncarcinogenic risks of contaminants in agricultural soils via multiple routes, deriving from ADD and the specific reference dose (RfD) with the following equations (USEPA 1989).
(5)
where RfD (mg·kg-1·day-1) is defined as the daily maximum permissible level of a pollutant that will not pose noncarcinogenic risks to residents during a lifetime, including the reference dose for ingestion and intake of contaminated food (RfD, mg·kg-1·day-1), RfDABS (RfDABS = RfDo × ABSGI; mg·kg-1·day-1) for dermal contact and reference dose of inhalation (RfCi; mg·m-3) for inhalation. ABSGI is the fraction absorbed in gastrointestinal tract in the critical toxicity study (unitless).
The noncarcinogenic risks of pollutants via non-dietary and dietary pathways were presented as HI, which was calculated as follows.
(6)
It is unlikely for the local residents to experience obvious adverse effect when HI < 1.
The carcinogenic risk assessment of each pollutant was calculated as follows.
(7)
where SF (mg·kg-1·day-1) consists of oral slope factors (SFO; (mg·kg-1·day-1) -1) for ingestion, SFO×ABSGI ((mg·kg-1·day-1) -1) for dermal contact and inhalation unit risk (IUR, (mg·m-3) -1) for inhalation.
Then simply add the risk from diverse exposure routes. It is considered that the carcinogenic risks of the pollutant is very low while the risk value is less than 10-6, low in the range of 10-6 and 10-4, moderate from 10-4 to 10-3, high from 10-3 to 10-1, and very high if it is over 10-1.
Parameter / Value / Reference
IRS / Adults / 100 / USEPA 2015
Children / 200
EF / Adults / 350 / USEPA 2015
Children / 350
ED / Adults / 26 / USEPA 2015
Children / 6
BW / Adults / 80 / USEPA 2015
Children / 15
AT / Adults / 9490 (noncarcinogenic) / USEPA 2015
25550 (carcinogenic)
Children / 2190 (noncarcinogenic)
25550 (carcinogenic)
IhR / Adults / 13.25a / USEPA 1997
Children / 12b
PEF / Adults / 1.4×109 / USEPA 2015
Children / 1.4×109
SA / Adults / 6032 / USEPA 2015
Children / 2690
AF / Adults / 0.07 / USEPA 2015
Children / 0.2
IRF / Adults / 258000 / National Bureau of Statistics of China 2015
Children / 86000
a It is the mean for male and female adults; b It is the mean for different ages of children.
Table SI-2. Parameters associated with different EDCs in the exposure risk assessment (USEPA 2015).
Compound / ABS / SFO / IUR / RfDo / RfCi / ABSGI
BBP / 0.1 / 1.9×10-3 / ─ / 2.0×10-1 / ─ / 1.0
DEP / 0.1 / ─ / ─ / 8.0×10-1 / ─ / 1.0
DEHP / 0.1 / 1.4×10-2 / 2.4×10-6 / 2.0×10-2 / ─ / 1.0
DnBP / 0.1 / ─ / ─ / 1.0×10-1 / ─ / 1.0
DnOP / 0.1 / ─ / ─ / 1.0×10-2 / ─ / 1.0
α-HCH / 0.1 / 6.3 / 1.8×10-3 / 8.0×10-3 / ─ / 1.0
β-HCH / 0.1 / 1.8 / 5.3×10-4 / ─ / ─ / 1.0
γ-HCH / 0.04 / 1.1 / 3.1×10-4 / 3.0×10-4 / ─ / 1.0
p,p’-DDD / 0.1 / 2.4×10-1 / 6.9×10-5 / ─ / ─ / 1.0
p,p’-DDE / 0.1 / 3.4×10-1 / 9.7×10-5 / ─ / ─ / 1.0
p,p’-DDT / 0.03 / 3.4×10-1 / 9.7×10-5 / 5.0×10-4 / ─ / 1.0
Table SI-3. Location information of the sampling areas.
Sampling area / GPS location
A / N 31°26'8.61" E 121°4'13.08"
B / N 31°12'33.88" E 120°57'35.92"
C / N 31°17'47.22" E 121°11'22.24"
D / N 31°23'59.90" E 121°0'46.83"
E / N 31°18'23.67" E 120°57'18.01"
F / N 31°23'37.45" E 121°8'34.22"
G / N 31°21'18.25" E 121°6'41.52"
H / N 31°16'23.13" E 121°5'21.26"
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References
USEPA (1997) Exposure Factors Handbook, EPA/600/P-95/002F; Environmental Protection Agency, Office of Research and Development: Washington, DC
USEPA (1989) Risk Assessment Guidance for Superfund, Vol. I: Human Health Evaluation Manual. EPA/540/1–89/002; Office of Solid Waste and Emergency Response, Washington, DC
USEPA (2015) Mid-Atlantic RISK Assessment. https://www.epa.gov/risk/regional-screening-levels-rsls-equations-november-2015
National Bureau of Statistics of China (2015) China Statistical Yearbook. China Statistic Press, Beijing
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