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8/14/2019 tp Ch Pht Trin Kh&Cn, tp 10,

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TP CH PHT TRIN KH&CN, TP 10, S07 - 2007

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NH GI HIN TR NG NHIM CH (Pb) TRONG RAU XANH THNH PHHCH MINH (TP.HCM)

Nguyn ThNgcnTr ng i hc Khoa h c Tnhin, HQG-HCM

(Bi nh n ngy 26 thng 01 n m 2006, hon ch nh s a ch a ngy 27 thng 02 n m 2007)

TM T T:Tr c s th ho, cng nghi p ho ngy cng cao cng v i vic pht tri n, xy d ng c s h t ng, dn chng cc n i v ngy cng ng, khi n cho di n tch t v n ngy cng b thu h p nn ng i dn ph i t n d ng t ng t c t tr ng rau c i,d a, c

Tuy nhin, do nhu c u th l n, ng i ta ch y theo l i nhun nn s d ng thu c tr su, di t c khng ng li u l ng, khng ng lc, khi n cho l ng thu c t n d cao ho cdng phn bn qu m c khi n cho l ng Nitrat cao, kim lo i n ng hin din, l nh ng m iquan ng i cho s c kho con ng i khi phi s d ng hng ngy. Trong ti ny, chng tinghin c u Ch (Pb).

1.GI I THIU

N c ta l m t n c c kh h u nhit i gi ma c thin nhin u i nn c ngu nrau qu di do quanh n m. Rau c tr ng nhiu n i p ng cho nhu c u tiu dnghng ngy, trong ni bt cho m t skhu vc tr ng rau v i sn l ng l n nhmt s tnh

pha Bc, Lt, ng Nai, Ty Ninh, Bnh D ng, Long An, Ti n Giang, cc huy n ngoithnh c a thnh ph HCh Minh nh : Hc Mn, C Chi, Bnh Chnh

Tuy nhin, hi n nay do ch y theo l i nhun v p ng nhu c u ca ng i tiu dng,ng i ta phi tng n ng sut, tng sn l ng rau xanh t mc thu nh p cao. Do v y, ng ita s dng ho ch t bo vthc vt, phn bn bao g m phn h u c v phn v c (phnho hc), hin sdng kh nhi u phn ho h c. Mt sn i cn s dng n c tcc knh r chc cha n c thi, t cc x nghi p, nh my d t nhum t i rau. V i tnh hnh ny, n gy hu qul n cho nh ng ng i tiu dng, quan tr ng l d l ng cc ch t c tch lu trong rau m hng ngy con ng i sdng, trong kim lo i nng nhCd, l kim lo i nngr t c nh h ng n sc khocon ng i.

Nhn thy c tm quan tr ng ca rau xanh v tnh c hi ca kim lo i nng i v i sckhocon ng i, nn trong ph m vi ti ny, chng ti kho st hm l ng kim lo i nngtrong rau xanh lu nh ng tr ng h p c d l ng v t mc qui nh. T , tm ranhng gii php h p l c nhng ci thin, xy d ng m hnh v n rau xanh, s ch h n,m bo sc khocho cng ng dn c , v c bit cho ng i tiu dng.

Do th i gian c h n nn chng ti ch t p trung nghin c u mt sm hnh tr ng rau xanh cc x thu c huyn Hc Mn, C Chi, Bnh Chnh c a Thnh ph HCh Minh.

1.1. Khi qut vrau an ton1.1.1. Khi ni m rau an ton

Nhng sn phm rau t i (bao g m cc lo i rau n l, c, thn, hoa, q a) c ch t l ngng nh c tnh c a chng, m c nhim cc ch t c hi v cc vi sinh v t gy h i khngv t qu ch tiu cho php, m bo an ton cho ng i tiu dng v nui tr ng c coi l raum bo an ton v sinh th c phm, gi tt l rau an ton (theo B Nng nghi p v Phttrin Nng thn).


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Sdng thu c theo nguyn t c 4 ng: ng thu c, ng lc, ng liu l ng, ng cchv m bo th i gian cch ly.

- Thu hoch, bao gi:Rau c thu ho ch ng chn, ho c b l gi, ho, qu b su,d dng Rau c r a k bng n c sch, ro n c, r i cho vo bao, ti s ch tr c khimang i tiu th ti cc c a hng, trn bao b ph i c phi u bo hnh, c a ch n i sn xutnhm m bo quyn l i cho ng i tiu dng.

2. VT LIU V PH NG PHP NGHIN C UMu: Rau cc lo i tu theo ma v , 1kg/m u rau, m i mu phn tch 2 l n: u ma, cu i

ma, ch n 3 huy n c tr ng nhiu rau, trong m i huyn chn x tr ng v cung c p rau chonhn dn thnh ph nhiu nht v c ng th ng phun x t thuc, s dng phn bn nhi u nhtnh huyn Hc Mn c x Tn Th i Nh, B im, Xun Th i S n, Xun Th i Th ng,Th i Tam Thn (n i tr ng rau torng ngh a a), ng Th nh (n i cnh bi rc); huyn BnhChnh c x a Ph c, Quy c, Bnh Chnh; huyn CChi c x Tn Ph Trung, TnThng H i, Tn An H i, Ph c Thnh.

Ph ng php nghin c u c th c hin 2 n i:- Ngoi th c a: Mun cng tc c hi u qu, cn phi i thc a kho st bn ngoi, cc hnng dn

tm hiu thm v cc m hnh tr ng rau xanh, iu tra v tnh hnh su b nh, phun x t thuc, s dng phn bn, n ng sut, sn l ng thu ho ch, din tch gieo tr ng. ng th i cng i cc x,

ph ng, huy n tm hiu thm v tnh hnh s n xut a ph ng, nt c tr ng ca mi a ph ng .

Ly mu rau v phn tch.- Trong phng th nghi m: Cng tc trong phng th nghi m gip cho k t qunghin c u

c chnh xc nh cc thng s , thng tin t nhng cuc phn tch m u.Sau khi c k t qu, chng ti bin so n, chun b vit bo co.

3. KT QUNGHIN C U, THO LUN3.1. Kho st:S lm dng ho ch t BVTV, c bit l thu c tr bnh, cng v i phn bn cc lo i nh:

phn rc, phn chu ng t chn nui cng nghi p, lm cho m t l ng kim lo i nng b r atri xu ng m ng, ao, h , sng, xm nh p vo mch n c ngm, gy nhi m. Cc kim lo inng tim n trong t tr ng cn th m th u, hoc t ngun n c thi thnh ph v khu cngnghi p chuy n ti p qua n c t i c rau xanh h p th.

3.2. K t quphn tch kim loi nng: Sau y l k t quphn tch kim lo i nng:

Bng 1:K t quphn tch kim lo i nng cc n i nghin c u

STT K hi u mu a im (x, huy n) Loi rau Ch tiu phn tchPb (mg/kg)1. H1 Tn Th i Nh, H c Mn D n 0,2262. H2 Tn Th i Nh, H c Mn C i ngt 0,0873. H3 Tn Th i Nh, H c Mn C i bdng 0,0764. H4 Tn Th i Nh, H c Mn C i xanh 0,0855. H5 Tn Th i Nh, H c Mn Hng cy 0,257


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Science & Technology Development, Vol 10, No.07 - 2007

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STT K hi u mu a im (x, huy n) Loi rau Ch tiu phn tchPb (mg/kg)6. H6 Tn Th i Nh, H c Mn Rau lang 0,1497. H7 B im, Hc Mn Rau mu ng 0,1588. H8 B im, Hc Mn M p 0,9. H9 B im, Hc Mn C tm 0,118

10. H10 B im, Hc Mn Rau r m 0,17711. H11 B im, Hc Mn Kh qua 0,07812. H12 Xun Th i Th ng, Hc Mn u c ve 0,12513. H13 Xun Th i Th ng, Hc Mn Hng qu 0,15914. H14 Xun Th i Th ng, Hc Mn C tm 0,02815. H15 Xun Th i Th ng, Hc Mn Ta t 0,06016. H16 Xun Th i Th ng, Hc Mn Rau ay 0,09117. H17 Xun Th i Th ng, Hc Mn M ng t i 0,04318. H18 Xun Th i S n, Hc Mn u b p 0,0619. H19 Xun Th i S n, Hc Mn u a 0,15320. H20 Xun Th i S n, Hc Mn Kh qua 0,03121. H21 Xun Th i S n, Hc Mn D a leo 0,01522. H22 Tn Th i Nh, H c Mn L l t 0,26423. H23 Th i Tam Thn, H c Mn M ng t i 0,11524. H24 Th i Tam Thn, H c Mn C i bxanh 0,10625. H25 Th i Tam Thn, H c Mn Gi p c 0,70526. H26 Th i Tam Thn, H c Mn X lch 0,06527. H27 Th i Tam Thn, H c Mn C i ngt 0,09028. H28 ng Th nh, Hc Mn C i xanh 0,08429. H29 ng Th nh, Hc Mn D n t 0,47930. H30 ng Th nh, Hc Mn D n 0,16131. H31 ng Th nh, Hc Mn X lch 0,02032. H32 ng Th nh, Hc Mn D n tiu 0,16133. H33 ng Th nh, Hc Mn M ng t i 0,03034. M1 a Ph c, Bnh Chnh D n xanh 0,07735. M2 a Ph c, Bnh Chnh D n 0,05936. M3 a Ph c, Bnh Chnh Rau ng 0,06537. M4 a Ph c, Bnh Chnh Rau mu ng 0,71938. M5 a Ph c, Bnh Chnh Hng qu 0,08539. M6 Qui c, Bnh Chnh u r ng 0,073

40. M7 Qui c, Bnh Chnh Rau m 0,09241. M8 Qui c, Bnh Chnh M ng t i 0,601


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STT K hi u mu a im (x, huy n) Loi rau Ch tiu phn tchPb (mg/kg)42. M9 Qui c, Bnh Chnh Rau mu ng 0,07043. M10 Qui c, Bnh Chnh C i xanh 0,02544. M11 Qui c, Bnh Chnh Hng qu 0,07445. M12 Bnh Chnh, Bnh Chnh Hng cy 0,12146. M13 Bnh Chnh, Bnh Chnh Ta t 0,40947. M14 Bnh Chnh, Bnh Chnh Rau r m 0,08348. M15 Bnh Chnh, Bnh Chnh Gi p c 0,10649. M16 Bnh Chnh, Bnh Chnh X lch 0,05350. M17 Bnh Chnh, Bnh Chnh Hnh l 0,07251. M18 Bnh Chnh, Bnh Chnh C i ngt 0,04752. M19 Bnh Chnh, Bnh Chnh Hng l i 0,08153. M1C Tn Ph Trung, C Chi Rau ay 0,09054. M2C Tn Ph Trung, C Chi H 0,07555. M3C Tn Ph Trung, C Chi C i bxanh 0,03856. M4C Tn Thng H i, CChi C ci tr ng 0,05557. M5C Tn An H i, CChi Rau mu ng 0,06358. M6C Ph c Thnh, CChi C i ngt 0,06259. M7C Ph c Thnh, CChi M ng t i 0,28260. M8C Ph c Thnh, CChi D n 0,05661. M9C Ph c Thnh, CChi Hng qu 0,205

Hm l ng cho php (mg/kg) 2,00

Phn tch t i Trung tm Th nghi m Mi tr ng, i hc Nng Lm Tp.HCM, 2005* Ng ng gi i hn kim loi n ng (Theo B Y t Vit Nam, 1995).

Qua k t quphn tch kim lo i nng cho th y tt c61 mu rau cc x thu c 3 huy nHc Mn, Bnh Chnh, C Chi u th p h n mc cho php, khng v t ng ng, tuy nhincn ch 2 m u H25 v M4 x Th i Tam Thn, huy n Hc Mn v x a Ph c, huy nBnh Chnh, hm l ng tn d Pb cao h n cc m u khc nhi u ln, thm ch hng ch c lnh n ngay trong cng m t a im nghin c u. Sau ny c iu kin, chng ti s thnghimti p nhiu ln nhng n i tr ng rau vng ngh a a, bi rc, v c ng tm hi u su thm v tnhh p thu Pb c a rau gi p c, rau mu ng

4. NHN XT, K T LUN,NGH 4.1. Nhn xt, k t lun4.1.1. V ho ch t bo v th c vt (BVTV)

Nh trn trnh by, a snng dn s dng ho ch t da trn c m tnh kinh nghi m, ttheo ch dn v t theo nguyn t c 4 ng l: ng liu, ng lc, ng cch, ng thu c.


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Cc thu c tr su cn dng trn rau hi n nay l DDT, BHC, Methyl parathion, Monitor,Demecron, Azodrin, Furadan, Vifuran, Yaltox, St trng linh, Demon, Kelthan, Bidrin,Thiodan, Endosol, Cyclodan, Thasodant, Thiodol, Tigiodan, Lannate..., c ng cn m t s t h sdng, nhng do h khng bi t hoc giu nhn hi u.

4.1.2. V hm l ng kim loi nng Nhn vo k t quphn tch hm l ng kim lo i nng Bng 1, chng ta c k t qu: Hm

l ng Pb theo TCVN: M c cho php trong rau c i l 2ppm th ng biu din trong cc hnh huyn Hc Mn, huyn Bnh Chnh v huyn CChi u d i mc cho php.

4.2.ngh Trong ph m vi nghin c u ca ti ny, chng ti nh n thy trong rau xanh sau khi

phn tch th Pb v n t tiu chu n, khng qu m c cho php. phng tr ng c do n phi rau c i b nhim c, ng i tiu dng c n phi lu sau

y:- Khng n rau c i c mi v , mu s c l.- R a sch rau c i tr c khi n. Ngm rau b ng n c r a rau q a hoc thuc tm.- Nu chn v m n p vung khi n u phn ho ch t BVTV n u cn st l i sbc

thot h i.

Ng i ta c th dng ph ng php sau y ty bho ch t trn rau c i:+ R a rau c i trong dung d ch gm 20 lt n c m v m t mung canh thu c mui(Bicarbonat Natri), ngm trong 15 pht s trung ho t 90-95% ho ch t c (lm m t tcdng hot ng).

+ i v i cc lo i rau c i ch c nhiu l th nh t bl ngoi, l trong ngm trong n csch khong 5 pht, n s loi b c thuc tr su, bnh trong rau c i t 50-60%. Sau khir a sch, em ngm trong n c sch chng 15 pht, lm nh vy gip lo i b t 7-35% hocht c hi trong rau.

+ Luc s rau trong n c nng s gim b t 50% thnhph n c hi (nn m n p ni).+ trnh s tc hi ca cc lo i thuc tr su mnh nht, tt nht nn b phn l

pha ngoi.+ C th ngm rau trong 4 lt n c c pha vi gi t thuc tm (Potassium permanganat).

+ R a rau b ng n c c vt vi gi t chanh.+ R a rau b ng n c mui (4 lt n c v i 2 mu ng c ph mu i).

AN ACTUAL STATE OF LEAD (Pb) PRESENTING IN THE GREENVEGETABLES IN HOCHIMINH CITY

Nguyen Thi Ngoc AnUniversity of Natural Sciences, VNU- HCM

ABSTRACT:With the rapid urbanization and industrialization in Hochiminh city, aswell as fast development in infrastructures, people from different places in the country keepcoming anh living in Hochiminh, causing to the decrease in agricultural land. As the result,

people have to utilize every area of land to cultivate cabbage, melon, egg- plant..etc


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However, due to high demand, farmers try to get more profits by using too muchinsecticides and herbicides, leading to high level of remainder in land. Morever, the overuse of

fertilize also causes high level of Nitrit and heavy metal in vegetables. This research will focuson level of lead (Pb) in green vegetables.

TI LIU THAM KHO

[1]. Argiculture Board and National Research Council Effect of pesticide on fruit and vegetable physiology, (1968).

[2]. Lee Sing Kong, From garden to kitchen: Grow your own fruit and vegetables,( 1994.).

[3]. BNng Nghi p v Pht tri n Nng thn, Danh mc thu c bo v th c vt c php, h n ch v c m s d ng Vit Nam, NXB Nng Nghi p, (2001).

[4]. Nguy n Th Ngc n, Nghin c u kim loi n ng c trong rau xanh cc v n rauthuc thnh ph HCh Minh (Bo co nghi m thu - ti c p B), (2006).

[5]. Nguy n Vn Uyn, Vng rau s ch - M t m hnh nng nghi p sinh thi c p bch, NXB Nng nghi p, (1995).U Ban Nhn Dn Thnh ph H Ch Minh, Ch ng trnh pht tri n rau an ton trn a bn thnh ph giai on 2002-2005, ( 2002).


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PHLC

DANH MC THUC BVTV CM S DNG VIT NAM(Ban hnh km theo Quy t nh s : 16/Q -BNN-BVTV ngy 12/03/2002

ca BNng Nghi p v Pht Tri n Nng Thn)STT Tn chung (Common Names)

Tn th ng phm (Trade Names) Thuc tr su, bo qun lm sn

1 Aldrin (Aldrex, Aldrite)2 BHC, Lindane (Gamma - HCH, Gamatox 15EC, 20EC, Lindafor, Carbadan 4/4G;

Sevidol 4/4G)3 Cadmium compound (Cd)4 Chlordane (Chlorotox, Octachlor, Pentichlor)5 DDT (Neocid, Pentachlorin, Chlophennothane)6 Dieldrin (Dieldrex, Dieldrite, Octalox)7 Eldrin (Hexadrin)

8 Heptachlor (Drimex, Heptamul, Heptox)9 Isobenzen10 Isodrin11 Lead compound (Pb)12 Methamidophos; (Dynamite 50SC, Filitox 70SC, Macter 50EC, 70SC, Monitor

50EC, 60SC, Isometha 50DD, 60DD, Isosuper 70DD, Tamaron 50EC)13 Methyl Parathion (Danacap M25, M40; Folidon - M50EC; Isomethyl 50ND;

Methapphos 40EC, 50EC; (Methyl Parathion) 20EC, 40EC, 50EC, Miloon 50EC;Proteon 50EC; Romethyl 50ND; Wofatox 50EC)

14 Monocrotophos: (Apadrin 50SL, Magic 50SL, Nuvacron 40SCW/DD, 50SCW/DD,Thunder 515DD)

15 Parathion Ethyl (Alkexon, Orthophos, Thiopphos)16 Sodium Pentachlorophenate monohydrat (Copas NAP 90G, PMD 90 b t,

P - NaF 90 b t, PBB 100 b t)17 Pentachlorophennol (CMM 7 d u lng, du tr mi M - 41.2 l ng)18 Phosphamidon (Dimecron 50SCW/DD)19 Polychlorocamphene (Toxaphene, Camphechlor)20 Strobane (Polychlorinate of Camphene)

Thuc tr bnh hi cy trng1 Arsenic compound (As) except Dinasin2 Captan (Captane 75WP, Merpan 75WP)

3 Captafel (Difolatal 80WP, Folcid 80WP)4 Hexachlobenzene (Anticaric, HCB)


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5 Mercury compound (Hg)6 Selenium compound (Se)

Thuc tr chut1 Talium compound (Tl)

Thuc tr c 1 2,4,5 T (Brechtex, Decamine, Veon)

Ghi ch: Cc ch phm c ch a Pentachlorophenol, Sodium Pentachlorophenate c gia cng, ch bin ti Vi t Nam c ti p tc sdng ht trnh ng, gy nhi mmi tr ng.


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M L NG KIM LOI CHO PHP TRONG CC LOI TH C PHM

n v tnh: mg/kg (ppm)STT Tn th c phm Asen

AsChPb

ngCu

ThicSn

K mZn

T.NgnHg

CadimiCd

AntimonSb

1 Sa v s n phmsa

0,5 2 30 40 40 0,05 1 1

2 Th t v sn phmtht

1 2 20 40 40 0,05 1 1

3 C v s n phm c 1 2 30 40 100 0,05 1 1

4 Du m 0,1 0,1 0,1 40 40 0,05 1 1

5 Rau qu 1 2 30 40 40 0,05 1 1

6 N c p rau qu 0,1 0,5 10 40 5 0,05 1 10,15

7 Ch v s n phm 1 2 150 40 40 0,05 1 1

8 C ph 1 2 30 40 40 0,05 1 1

9 Cacao v s n phm 5 2 70 40 40 0,05 1 1

10 Gia v 1 2 30 40 40 0,05 1 1

11 N c chm 0,2 2 30 40 40 0,05 1 1

12 ung c r udm

0,5 0,5 5 40 2 0,05 1 0,15

13 N c gii kht: a.Cn pha long

b.Dng ngay

0,1 10,2

102

4040

255

0,050,05

11

0,150,15

14 Thc n tr em ch bin sn, bt dinhd ng, thc n tr em ng h p

0,1 0,5 5 40 40 0,050,05

1 1

15 h p cc lo i(khng k cc th c phm nhm 14)

250

Ghi ch: Gi i hn khi pha long s n phm.L ng n vo t i a cho php: (Tnh theo g/kg tr ng l ng c th/mu)

(PTWI)As Pb Cd Hg15 25 73,3(TnhtheoMethylthu ngn)

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