J Korean Soc Appl Biol Chem (2012) 55, 423−427 DOI 10.1007/s13765-012-1027-7

SHORT COMMUNICATION

Investigation on Polychlorinated Dibenzo-p-dioxins, Polychlorinated Dibenzofurans and Dioxin-like Polychlorinated Biphenyls in Korean Fruits and Dietary Intake Estimation Geun-Hyoung Choi · Dal-Soon Choi · Su-Myeong Hong · Oh-Kyoung Kwon · Hee Soo Eun · Jeong-Han Kim · Jin Hyo Kim

Received: 17 November 2011 / Accepted: 28 February 2012 / Published Online: 30 June 2012 © The Korean Society for Applied Biological Chemistry and Springer 2012

Abstract Contamination levels of 17 polychlorinated dibenzop-dioxins (PCDDs)/polychlorinated dibenzofurans (PCDFs) and 12 dioxin-like polychlorinated biphenyls (DL-PCBs) were investigated on six major fruits consumed in Korea. Dioxin level was monitored on whole fruits. Average concentrations of PCDD/ Fs were 0.042 pg/g fresh weight (f.w.) (apple), 0.0094 pg/g f.w. (grape), 0.1843 pg/g f.w. (mandarin orange), 0.2282 pg/g f.w. (peach), 0.1491 pg/g f.w. (pear), and 0.1330 pg/g f.w. (persimmon). For DL-PCBs, the average concentrations were 0.0932 pg/g f.w. (apple), 0.2649 pg/g f.w. (grape), 1.5437 pg/g f.w. (mandarin orange), 0.1942 pg/g f.w. (peach), 0.4591 pg/g f.w. (pear), and 0.4396 pg/g f.w. (persimmon). The major toxic equivalency (TEQ) contributors were identified as 1,2,3,7,8-pentachlorodibenzop-dioxin in PCDD and 2,3,4,7,8-pentachlorodibenzofuran in PCDFs. Most residual DL-PCBs showed no contribution to total TEQ values. The lowest TEQ level was recorded in peach (0.0161 pg-TEQWHO/g f.w.), and the highest TEQ level was found in mandarin orange (0.0448 pg-TEQWHO/g f.w.). Total estimated daily intake (EDI) of dioxins from the six fruits was calculated at 3.8159 pg-TEQWHO/day, which is 1.59% of Korean tolerable daily intake based on 60 kg body weight.

G.-H. Choi · D.-S. Choi · S.-M. Hong · O.-K. Kwon · J. H. Kim (
) Chemical Safety Division, National Academy of Agricultural Science, Rural Development Administration, Suwon 441-707, Republic of Korea E-mail: [email protected] H. S. Eun Organochemicals Division, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai, Tsukuba, Ibaraki 305-8604, Japan J.-H. Kim School of Agricultural Biotechnology, Seoul National University, Seoul, 151-742, Republic of Korea

Keywords fruits · Korea · polychlorinated biphenyls · polychlorinated dibenzo-p-dioxins · polychlorinated dibenzofurans

Persistent organic pollutants (POPs) are organic compounds that are non-degradable, long-range transportable, and bioaccumulated toxic chemicals. They include several organochlorine pesticides and industrial byproducts such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) (Grassi et al., 2010). Among the POPs, PCDD/Fs and dioxin-like PCBs (DL-PCBs) are highly considered as organochlorine POPs due to their notable toxicities. Thus, the World Health Organization (WHO) has set the tolerable daily intake (TDI) for dioxins at 4 pg-TEQWHO/kg body weight (b.w.)/day (European Commission, 2000), and adopted by the Korean Food and Drug Administration (Kim et al., 2008). The main source of dioxin exposure for human is known to be food contamination in non-occupational exposure person (Parzefall, 2002; Baars et al., 2004). A number of researchers investigated the contamination of PCDD/Fs and DL-PCBs in livestock products (Bernard et al., 1999; Guruge et al., 2005), dairy products (De Mul et al., 2008), marine products (Edwards, 2004; Moon et al., 2010), and farm products (Tard et al., 2007; Grassi et al., 2010). However, information on the background concentration level of dioxins in agricultural fresh food is scarce, because the survey was mostly focused on fat-rich product and cereals but not on fresh fruits. As part of ongoing studies on dioxin contamination in Korean fresh food, the present study determined the levels of 17 PCDD/Fs, 12 DL-PCBs using the HRGC/HRMS in the six major Korean fruits, including apple, grape, mandarin orange, peach,

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pear, and persimmon that were collected from 36 orchards in Korea in 2009, representing around 74% of total Korean fruits consumption (Korean CDC, 2008). In this research, 7 apples, 6 grapes, 3 mandarin oranges, 6 peaches, 7 pears, and 7 persimmons were collected from each major producing district in Korea. The whole fruit, without peeling and washing, was used, except for peach, in which the core was removed. Each fruit was chopped and stored in the freezer before analysis. All analytical samples for dioxins were prepared according to the method of Kim et al. (2008) with several modifications. Briefly, 50 g of samples were extracted by homogenization with acetone/n-hexane, filtered, and spiked with a mixture of 13C12labelled 29 PCDD/Fs and DL-PCBs congeners (Wellington Laboratories, Canada). The extract was transferred to a separation funnel, followed by washing the organic phase with saturated

sodium chloride. Concentrated sulfuric acid was added and mixed to the organic phase to eliminate the pigment. The organic phase was then washed with distilled water, and concentrated under reduced pressure. Clean-up procedure was performed with the PowerPrep automated system (Fluid Management System Inc., USA) equipped with three types of columns including silica, alumina and activated carbon. After washing with hexane, monoand di-ortho, PCBs were eluted with 2 and 50% dichloromethane (Fraction 1). Then, as injection standard solution, 13C12-labeled PCBs IUPAC 70, 111 and 138 were spiked to Fraction 1. PCDD/ Fs and non-ortho PCBs were eluted with toluene (Fraction 2). For Fraction 2, 13C12-labelled 1,2,3,4,6-PentaCDF and 1,2,3,4,6,8,9HeptaCDF with above labeled PCB congeners were added. Quantification and identification of PCDD/Fs and DL-PCBs were performed with HRGC-HRMS system. The analysis was conducted with DB-5MS (60 m × 0.25 mm × 0.25 µm) and SP-

Table 1 Residual concentrations of PCDDs/PCDFs congeners in Korean fruit PCDDs/Fs (pg/g f.w.) Range (mean ± SD) Apple (n=7)

Grape (n=6)

Mandarin orange (n=3)

Peach (n=6)

Pear (n=7)

Persimmon (n=7)

N.D.

N.D. 0–0.0423 (0.0083±0.0173)

0–0.0182 (0.0091±0.0129) 0–0.0302 (0.0151±0.0213)

0–0.0224 (0.0037±0.0091) 0–0.0355 (0.0059±0.0145)

0–0.0173 (0.0025±0.0065) 0–0.0218 (0.0031±0.0082)

N.D.

N.D.

N.D.

N.D.

N.D.

1,2,3,6,7,8-HxCDD

N.D.

N.D.

N.D.

N.D.

1,2,3,7,8,9-HxCDD

N.D.

0–0.0347 (0.0173±0.0245)

1,2,3,4,6,7,8-HpCDD

N.D.

OCDD

N.D.

0–0.1286 (0.0247±0.0520) 0–0.0794 (0.0113±0.0324) 0–0.1646 (0.0435±0.0790) 0–0.0487 (0.0242±0.0218) 0–0.0286 (0.0041±0.0117) 0–0.0898 (0.0294±0.0401) 0–0.0424 (0.0061±0.0173)

0–0.0539 (0.0270±0.0381) 0.0409–0.0471 (0.0440±0.0044)

0–0.0459 (0.0076±0.0187) 0–0.0958 (0.0370±0.0434) 0–0.3241 (0.1351±0.1131) 0–0.0504 (0.0146±0.0230)

N.D.

N.D.

0.0178–0.0550 (0.0364±0.0263)

0–0.0434 (0.0072±0.0277)

0–0.0217 (0.0031ϖ0.0082) 0–0.0721 (0.0200±0.0280) 0–0.0921 (0.0186±0.0354) 0–0.2227 (0.0318±0.0842) 0–0.0289 (0.0109±0.0116) 0–0.0230 (0.0049±0.0091) 0–0.0760 (0.0461±0.0233)

0–0.0115 (0.0016±0.0043) 0–0.0151 (0.0078±0.0073) 0–0.0215 (0.0031±0.0081) 0–0.0360 (0.0051±0.0136)

0–0.0410 (0.0059±0.0155)

1,2,3,4,7,8-HxCDD

N.D.

N.D.

N.D.

2,3,7,8-TCDD 1,2,3,7,8-PeCDD

2,3,7,8-TCDF

0–0.0387 (0.0100±0.01719)

1,2,3,7,8-PeCDF

N.D.

2,3,4,7,8-PeCDF

0.0462–0.0650 (0.0548±0.0068)

N.D.

1,2,3,4,7,8-HxCDF

N.D.

1,2,3,6,7,8-HxCDF

N.D.

N.D.

N.D.

1,2,3,7,8,9-HxCDF

N.D.

N.D.

N.D.

2,3,4,6,7,8-HxCDF

N.D.

N.D.

1,2,3,4,6,7,8-HpCDF

N.D.

1,2,3,4,7,8,9-HpCDF OCDF

N.D. N.D. 0.0462−0.1448 (0.0042±0.0133)

Sum of PCDDs/PCDFs

0–0.0574 (0.0082±0.0234) N.D. N.D. 0−0.6817 (0.0094±0.0132)

N.D. N.D. N.D. 0–0.0205 (0.0127±0.0089) 0–0.0362 (0.0090±0.0136) 0.0488–0.0645 (0.0571±0.0067) 0–0.0266 (0.0038±0.0100)

0–0.0264 (0.0044±0.0108) 0–0.0755 (0.0126±0.0308)

N.D.

N.D.

0–0.0319 (0.0046±0.0121)

N.D.

0–0.0707 (0.0354±0.0500)

N.D.

N.D.

N.D.

N.D.

N.D.

N.D. N.D. 0.0587−0.3099 (0.1843±0.0155)

N.D. N.D. 0−0.7194 (0.2282±0.0033)

0–0.0248 (0.0035±0.0094) N.D. N.D. 0−0.6322 (0.1491±0.0132)

0–0.0251 (0.0036±0.0095) N.D. N.D. 0.0634−0.1647 (0.1330±0.0389)

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2331 (60 m × 0.25 mm × 0.25 µm). The HRGC-HRMS program was operated in electron impact ionization (EI) mode at a resolution of more than 10,000 using multiple ion detection (MID). We used the non-detects as equal to zero. Toxic equivalent (TEQ) levels of dioxins were expressed in pg-TEQWHO/gram using the appropriate WHO toxic equivalency factor (WHO-TEF) (Van den Berg et al., 2006). The contamination level of PCDD/Fs were 0.0042 pg/g fresh weight (f.w.) in apple, 0.0094 pg/g f.w. in grape, 0.1843 pg/g f.w. in mandarin orange, 0.2282 pg/g f.w. in peach, 0.1491 pg/g f.w. in pear, and 0.1330 pg/g f.w. in persimmon (Table 1). The average contamination residues of PCDD/Fs, in ascending order, are peach, mandarin orange, pear, persimmon, grape and apple. The most abundant contaminant were 1,2,3,7,8-PeCDD for PCDDs, and 2,3,7,8-TCDF and 2,3,4,7,8-PeCDF for PCDFs. On the other hand, the contamination level of DL-PCBs were 0.0932 pg/g f.w. in apple, 0.2649 pg/g f.w. in grape, 1.5437 pg/g f.w. in mandarin orange, 0.1942 pg/g f.w. in peach, 0.4591 pg/g f.w. in pear, and 0.4396 pg/g f.w. in persimmon (Table 2). Mandarin orange showed the highest average residue of DLPCBs. The most abundant contaminant was 3,3',4,4'-TeCB (PCB 77) for DL-PCBs. In this experiment, 1,2,3,4,7,8,9-HpCDF and OCDF in PCDD/ Fs, and 2,3,3',4,4'-PeCB (PCB 105), 2,3,4,4',5-PeCB (PCB 114), 2',3,4,4',5-PeCB (PCB 123), 2,3,3’,4,4’,5-HxCB (PCB 156), 2,3,3',4,4',5'-HxCB (PCB 157), 2,3',4,4',5,5'-HxCB (PCB 167) and 2,3,3',4,4',5,5'-HpCB (PCB 189) were not detected on the major fruits. The congener pattern of PCDD/Fs and DL-PCBs in fruits

was similar to the atmosphere’s congener pattern obtained by Shin et al. (2011). They reported that DL-PCBs did not show significant seasonal and spatial variations in the congener profile, whereas the congener patterns of 17 PCDD/Fs were different by sampling season and area. The TEQ levels of the six fruits, in descending order, are: mandarin orange (0.0448 pg-TEQWHO/g f.w.) > persimmon (0.0293 pg-TEQWHO/g f.w.) > grape (0.0257 pg-TEQWHO/g f.w.) > apple (0.0232 pg-TEQWHO/g f.w.) and pear (0.0236 pg-TEQWHO/g f.w.) > peach (0.0161 pg-TEQWHO/g f.w.) (Table 3). The most common TEQ contributors were 2,3,4,7,8-PeCDF in apple, grape, pear and persimmon, and 1,2,3,7,8-PeCDD in mandarin orange and peach. The TEQ contributors of DL-PCBs such as 3,3',4,4',5PeCB (PCB 126) and 3,3',4,4',5,5'-HxCB (PCB 169) were only identified in grape. The TEQ contribution ratio of PCDFs was greater than PCDDs or DL-PCBs in the major six fruits, except mandarin orange and peach, and the TEQ contribution ratio of DL-PCBs (10.9 %) was recorded only in grape (Fig. 1). The estimated daily intake (EDI) for population was calculated by multiplying the measured TEQ concentration based on the food consumption data of the local residents that were investigated (Shin et al., 2011), and the results were divided by 60 to obtain average daily exposure per kg of body weight (WHO/FAO, 2005). The daily intake of dioxins from the six fruits were estimated at 0.7215 (apple), 0.2981 (grape), 1.4650 (mandarin orange), 0.2174 (peach), 0.5192 (pear), and 0.5948 pg-TEQWHO/day (persimmon). The total EDI of dioxins from the six fruits were 3.8159 pgTEQWHO/day for Koreans (Table 4).

Table 2. Residual concentrations of DL-PCB congeners in Korean fruits PCBs (pg/g f.w.) Range (mean ± SD) Apple (n=7)

Grape (n=6)

Mandarin orange (n=3)

Peach (n=6)

Pear (n=7)

Persimmon (n=7)

3,3',4,4'-TeCB (77) §

0–0.1489 (0.0932±0.0645)

0.1895–0.2175 (0.2035±0.0198)

0.1173–0.2734 (0.1942±0.0611)

0–0.2292 (0.1077±0.1047)

0–0.2275 (0.1032±0.0852)

3,4,4',5-TeCB (81)

N.D.

N.D.

N.D.

N.D.

N.D.

3,3',4,4',5-PeCB (126)

N.D.

N.D.

N.D.

N.D.

N.D.

3,3',4,4',5,5'-HxCB (169)

N.D.

N.D.

N.D.

N.D.

N.D.

2,3,3',4,4'-PeCB (105) 2,3,4,4',5-PeCB (114)

N.D. N.D.

0.1325–0.4220 (0.1913±0.1079) 0–0.1086 (0.0155±0.0443) 0–0.1040 (0.0149±0.0424) 0–0.1600 (0.0432±0.0783) N.D. N.D.

N.D. N.D.

2,3',4,4',5-PeCB (118)

N.D.

N.D.

N.D. N.D. N.D. N.D. N.D. 0–0.1489 (0.0932±0.0645)

N.D. N.D. N.D. N.D. N.D. 0–0.7946 (0.2649±0.0548)

N.D. N.D. 1.1294–1.5510 (1.3402±0.2981) N.D. N.D. N.D. N.D. N.D. 1.3188–1.7685 (1.5437±0.3860)

N.D. N.D. 0–1.2620 (0.3513±0.6003) N.D. N.D. N.D. N.D. N.D. 0–1.4912 (0.4591±0.1033)

N.D. N.D. 0–1.2462 (0.3364±0.5758) N.D. N.D. N.D. N.D. N.D. 0–1.4736 (0.4396±0.0989)

2',3,4,4',5-PeCB (123) 2,3,3',4,4',5-HxCB (156) 2,3,3',4,4',5'-HxCB (157) 2,3',4,4',5,5'-HxCB (167) 2,3,3',4,4',5,5'-HpCB (189) Sum of DL-PCBs §

( ) IUPAC (International Union of Pure and Applied Chemistry) number

N.D. N.D. N.D. N.D. N.D. N.D. 0.1173–0.2734 (0.1942±0.0561)

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Table 3. Average levels of the dioxin (PCDDs and PCDFs) and DL-PCBs in fruits (pg-TEQWHO/g f.w.) Apple

Grape

Mandarin orange

Peach

Pear

Persimmon

2,3,7,8-TCDD 1,2,3,7,8-PeCDD 1,2,3,4,7,8-HxCDD 1,2,3,6,7,8-HxCDD 1,2,3,7,8,9-HxCDD 1,2,3,4,6,7,8-HpCDD OCDD 2,3,7,8-TCDF 1,2,3,7,8-PeCDF 2,3,4,7,8-PeCDF 1,2,3,4,7,8-HxCDF 1,2,3,6,7,8-HxCDF 1,2,3,7,8,9-HxCDF 2,3,4,6,7,8-HxCDF 1,2,3,4,6,7,8-HpCDF 1,2,3,4,7,8,9-HpCDF OCDF 3,3',4,4'-TeCB (77) 3,4,4',5-TeCB (81) 3,3',4,4',5-PeCB (126) 3,3',4,4',5,5'-HxCB (169) 2,3,3',4,4'-PeCB (105) 2,3,4,4',5-PeCB (114) 2,3',4,4',5-PeCB (118) 2',3,4,4',5-PeCB (123) 2,3,3',4,4',5-HxCB (156) 2,3,3',4,4',5'-HxCB (157) 2,3',4,4',5,5'-HxCB (167) 2,3,3',4,4',5,5'-HpCB (189)

0 0.0059±0.0155 0 0 0 0 0 0.0010±0.0017 0 0.0164±0.0020 0 0.0002±0.0005 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0.0083±0.0173 0 0 0.0025±0.0052 0.0001±0.0003 0 0.0024±0.0022 0.0001±0.0004 0.0088±0.0120 0.0006±0.0017 0 0 0 0.0001±0.0002 0 0 0 0 0.0015±0.0042 0.0013±0.0024 0 0 0 0 0 0 0 0

0.0091±0.0129 0.0151±0.0213 0 0 0.0017±0.0025 0 0 0.0044±0.0004 0 0.0109±0.0079 0 0 0 0.0035±0.0050 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0.0037±0.0091 0.0059±0.0145 0 0 0.0008±0.0019 0.0004±0.0004 0 0.0015±0.0050 0 0.0022±0.0130 0 0.0004±0.0011 0.0013±0.0076 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0.0025±0.0065 0.0031±0.0082 0 0.0003±0.0009 0.0020±0.0028 0.0002±0.0003 0 0.0011±0.0012 0.0001±0.0003 0.0138±0.0070 0 0 0.0005±0.0012 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0.0016±0.0043 0.0078±0.0073 0.0003±0.0008 0.0005±0.0014 0 0 0 0.0013±0.0009 0.0003±0.0004 0.0171±0.0020 0.0004±0.0010 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

TEQPCDDs/PCDFs

0.0232±0.0041

0.0229±0.0028

0.0448±0.0047

0.0161±0.0016

0.0236±0.0034

0.0293±0.0044

TEQDL-PCBs

0

0.0028±0.0005

0

0

0

0

Total TEQ

0.0232±0.0041

0.0257±0.0028

0.0448±0.0047

0.0161±0.0016

0.0236±0.0034

0.0293±0.0044

Based on the results, the dioxin exposure of an average Korean male was estimated at 0.0636 pg-TEQWHO/kg b.w./day from the six fruits, with the fruits contributing 1.59% of Korean TDI. However, the real dietary exposure to dioxins would be lower than the estimated figures because the TEQ levels in this experiment were investigated using whole fruits including both edible and inedible portion. Acknowledgment This work was supported by a grant from the Research Program for Agricultural Science & Technology Development (Project No. PJ0053022011 and PJ0063382011), National Academy of Agricultural Science, Rural Development Administration, Republic of Korea.

References Fig. 1 The average TEQ contribution of dioxins (PCDDs, PCDFs and DL-PCBs) in six major Korean fruits.

Baars AJ, Bakker MI, Baumann RA, Boon PE, Freijer JI, Hoogenboom LAP

J Korean Soc Appl Biol Chem (2012) 55, 423−427

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Table 4. Estimated daily intake (EDI) to the dioxins of Korean fruits Daily Intake* Apple Grape Mandarin orange Peach Pear Persimmon Total TEQ

31.1 g 11.6 g 32.7 g 13.5 g 22.0 g 20.3 g

EDI dioxins (pg-TEQWHO/day/person) PCDDs

PCDFs

DL-PCBs

Total

0.1835 0.1264 0.8469 0.1458 0.1782 0.2091 1.6900

0.5380 0.1392 0.6180 0.0716 0.3410 0.3857 2.0935

0 0.0325 0 0 0 0 0.0325

0.7215 0.2981 1.4650 0.2174 0.5192 0.5948 3.8159

*Daily intake values were referenced from Korea National Health and Nutrition Examination Survey in 2007 (Korean CDC, 2008).

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