KHOA HOC, CONG NGHE CHUYEN GIAO OANH GIA SO BO HAIVILaONG CAC OONG Vj PHONG XA (U 238, TH 232, K 40, CS 137) TRONG K H O N G KHI TAITP HO CHl MINH DO TAC OONG CUA VIEC 0 0 THJ HOA • I I I PGS TS DINH[.]
Trang 1KHOA H O C , CONG NGHE - CHUYEN GIAO
OANH GIA SO BO HAIVILaONG CAC OONG Vj PHONG XA
TAITP HO CHl MINH DO TAC OONG CUA VIEC 0 0 THJ HOA
Vien Moi trudng va Tai nguyen
ThS NGUYfeN THI THUY VAN
Dal hgc Khoa hgc Tu nhien TP Ho Chi Minh
Tom tat: Chat lirang moi tnrdng khong khi la mot trong cac yeu to quan trong quyet drnh chat
lugng cugc song vl no anh hwang true tiep gen sire khoe con nguai Tu" sir can thiet nay TP HCM ga
sdm xay gi/ng mang ludi quan trac 6 nhiim khong khi vai cac thong so quan trac nhu: SO^, NO^, CO,
O3, NO 2, benzen, xylene, toluen, chi, hui tong, tieng on Ngoai cac thong so ga neu, ham lugng phong
xa trong khong khi cung la mgt thong so can gugc khao sat va ganh gia mgt each thuang xuyen, gac
biet la tai cfp cao tir 1 gen 3m tinh tir mat gat Tuy nhien, cho gen nay ham lugng phong xa trong khong
khi van chua gugc khao sat mot each eo he thong
Nhom tac gia ga tien hanh khao sat va ganh gia sa bg ham lugng cac gSng vi phong xa (U-238,
Th-232, K-40, Cs-137) trong khong khi tai TP HCM Dong thai chung toi cung gua ra mgt sSgS xuat
gang luu y trong viec giam sat va giam thieu 0 nhiem moi truang (ONMT) khong khi tai TP HCM
Abstract: The quality of air is one of an Important factors which affects gireetly to the human
health For this reason, Hochimlnh city has establisheg air polution monitoring stations with some
main monitoring paramaters, such as: SO^, NO^, CO, 0^, NO^, benzene, xylene, toluene, /ead, TSP
noise Besige those parameters, the ragio-active Isotopes concentration in the air is also a parameter
which Is geserveg to stugy frequently, especially In the high from 1 to 3 meter above the earth's surface
However, untill now the radio-active isotopes concentration In the air hasn't studleg systematically
To take full advantage of the nuclear analysis technology, we studied and evaluated the status of
the radio-active isotopes concentration (U-238, Th-232, K-40, Cs-137) in the air in Hochimlnh city
Form that point, we proposed some remarkable solutions to supervise and minimize the air population
in Hochimlnh city
I CAC NGHIEN CUU TRONG VA NGOAI NUtfC
Tren the gidi, viec Ung dung cac ky thuat hat nhan de
xac djnh ham lupng cac ddng vi phdng xa trong khdng khf
da dupe tie'n hanh tai nhieu nudc nhu My [6], Nga [7], Nhat
[8], Pakistan [9] Cac ke't qua thu dupe tU cac nghien eUu
nay da cung cap cho cac nha khoa hpc nhirng dU lieu vd
eiing quan trpng de danh gia xu hudng cung nhu nhUng
anh hudng ciia chiing den sUc khde ciia con ngudi trong
thdi ky phat trid'n rat nhanh cua khoa hpc - cdng nghe
Tai Viet Nam, trong thdi gian qua cac don vj true thudc
Vien Nang lupng Nguyen tir Viet Nam da thuc hien mdt sd
cdng trinh nghien curu ham lupng phdng xa trong nhilu
ddi tupng mdi trudng khac nhau nhu trong dat, thue vat [1],
luong thue [2], thuc pha'm [3] Tuy nhien, viec danh gia
hoat dp cac ddng vi phdng xa trong khdng khf van chua dupe quan tam dung mUc, cu the la tai TR HCM chi cd 1 tram quan trac su sa lang phdng xa toan eau, dat d dp cao 25m Viec danh gia ham lupng phdng xa trong Idp khdng khi ma con ngudi thudng xuyen sinh sdng (tU b l mat da't den dp cao khoang 3m tren mat da't) ma van chua dupe tiln hanh
II muc TIEU, NOI DUNG, PHUfONG PHAP NGHIEN CUU
11.1 Muc tieu nghien CL^
Muc tieu dat ra cQa viec nghien ciru la dua trdn cac sd lieu thu thap, kit qua do dac tai hien trudng de danh gia hien trang ham lupng eae ddng vj phdng xa (K-40, U-238, Th-232, Cs-137) trong khdng khf tai 2 quan (Quan 1, Quan
11/2010 BAO HO LAO DQNG 13
Trang 2KHOA H O C , CONG NGHE - CHUYEN GIAO I
Tan Phii), TR HCM, tren cd sd dd d l xua't cac bien phap
giam sat va giam thieu ONMT khdng khf do cac chat phdng
xa
11.2 No! dung nghien cuTu
De dat dupe muc tieu de ra, ndi dung nghien ciru
chiing tdi da tien hanh bao gdm:
- Tdng quan ve d nhiem khdng khf do K-40, U-238,
Th-232, Cs-137;
- Khao sat thue dja va lua ehpn vi tri lay miu, thie't lap
sodd vj trila'y mau;
- Oanh gia so bd hien trang ONMT khdng khf do eae
chat phdng xa trong khu vue khao sat;
- 0 1 xua't cac bien phap giam sat va giam thieu ONMT
khdng khf do cac chat phdng xa
11.3 Phi/dng phap nghien ciiru
a Nghien ciru ly thuyet
- Suu tam tai lieu cd lien quan nhu cac de tai nghien
eiru khoa hpc, cac bai bao, saeh, cac bao cao kit qua
quan trac mdi trudng khdng khf, eae tieu chuan Viet Nam
hien hanh
- Tham khao y kie'n eua cac chuyen gia trong viec lua
ehpn dja diem lay miu, thu thap miu, do dae miu, dae
biet la xir ly va danh gia kit qua phan tfch mau
- Tdng hpp, phan tfch tai lieu thu thap, xir ly sd lieu
b Nghien ciru thuc nghiem
- Khao sat hien trang
khu vuc nghien cifu, lua
chon vjtriliy mau, tien hanh
thu thap miu
- Sir dung phan mIm
Mapinfo de sd hda ban dd
va trinh bay so bd vj tri lay
miu
- Do dac miu, xir ly sd
lieu
- So sanh ke't qua do
dac vdi eae tieu chuan va
cac ket qua giam sat sa lang
phdng xa toan cau ciia Vien
Nghien cifu hat nhan de
nhan xet danh gia
c Lay mau tai hien
trudng
Do thdi gian va kinh phf
cd han, chung tdi ehi ehpn
ra hai quan de tie'n hanh lay
mau la Q.Tan Phu (quan
dang trong qua trinh dd thj
hda manh me nen tde dp xay
N.I Ul 2007
dung nha cira, dudng xa hien nay kha cao) va Q.I (khu dan eu hien hUu) Tai mdi quan, chung tdi ehpn 2 dja diem
de tiln hanh lay miu (xem Hinh 1), eu the:
- Quan 1: miu dupe lay tai Trung tam Hat nhan TR HCM (TTHN), Sd Tai nguyen va Mdi trudng (Sd TN-MT)
- Quan Tan Phu: miu dupe lay tai Khu cdng nghiep Tan Binh (KCN T Binh) va Trung tam Y te Quan Tan Phu (TTYT T Phu)
Do TR HCM nam trong vung nhiet ddi gid mua, can xich dao nen thdi tilt tai day chia ra 2 mua rd ret: mua mua (tUthang5-thang 10); muakhd(tUthang 11 -thang4nam sau) nen chung tdi da lua ehpn lay miu theo hai mua
Ngoai ra, de giam thieu sai sd cua miu thu thap chung tdi
da tien hanh thu thap miu lap: tai mdi dja diem chung tdi tie'n hanh thu thap 3 mau cho mdi mua, nhu vay tdng sd miu chung tdi da thu thap la 24 miu/2 mua/4 dja diem
Viec thu gom miu dupe tie'n hanh tren phim loc chuyen dung Pallflex membrane filters thdng qua he may hut khf Ecotech hivol 3000, loai may bui thu gom la bui lo limg
tdng cdng TSP Do cao lay mau each mat dat 1 m, la dp eao
ma khdng khf bj xao trdn nhilu nha't do hoat ddng eiia con ngudi
d Phan tich mau
Viec phan tfch miu dupe tie'n hanh tren he may phan tfch phd gama diing detectd ban din sieu tinh khiet HPGe
sa BO \1 TRi L.4'V Ukv Bl'I K Hi H wh i
12
Q.Go Va'p
<lhi (Hu
Rauli gi»'i qliau, hliyeu
Klui vH'c utJlii^n cii'll
Vi rri hy ui.iii
Nyni>'i thuc hieu ; NguyeuTWTlluy V.iu Nyirofi hii'tfug tl.i ii: PGS.TS f>iuh Xua u Tlu ut
Colli fai lien : E.iu (tii di.i hiuhTi) HCM I< le 1 : 50.000
H/'n/i 1: Soldo vj tri lay mau bui khi
Trang 3KHOA H O C , CONG NGHE - CHUYEN GIAO
Bang 1 Ke't qua pt
Ky
hieu
mau
M4
M5
M6
M7
M9
M10
Mil
M12
M13
M14
M15
M16
M17
M18
M19
M21
M25
M26
M27
M28
M29
M30
Ncfi lay mau
Sd TN-MT Q.1
Sd TN-MT Q.I
Sd TN-MT Q.1
TTYT T Phu
TTYT T Phu
KCN T Binh
KCN T Binh
KCN T Binh
TTHN (Q.I)
TTHN (Q.I)
TTHN (Q.1)
Sd TN-MT Q.1
Sd TN-MT Q.1
Sd TN-MT Q.1
KCN T Binh
KCN T Binh
TTYTTPhu
TTYT T Phu
TTYT T Phu
TTHN Q.1
TTHN Q.1
TTHN Q.1
lan tich ham iWcfng phong xa trong mau bui khi tai Quan Tan Phu
Thdi diem lay mau (thang /nam)
06/06 06-07/06 07/06 07/06 07-08/06 08/06 08/06 08-09/06 09-10/06 10/06 10/06 11/06 11/06 12/06 12/06 12/06-01/07 01-02/07 02/07 02/07 02-03/07 03/07 03-04/07
The tfch miu
(m')
4925
4176
3866
4570
4338
4700
4182
4406
3049
4099
3783
4717
4406
4097
4397
3525
4613
4228
4818
4808
5270
5122
Khoi luong bui
(g)
0,9 0,78 0,67 0,98 0,86 0,76 0,83 0,97 0,32 0,57
0 , ^
0,98 0,95 0,89 0,97 0,74 1,2 1,12 1,13 0,63 0,95 0,74
U-238 (10'Bq/m')
Ham lUtfng
1,52 1,37 1,4 1,92 1,64 1,76 1,61 1,68 2,16 2,39 1,73 2,23 2,05 2,2 1,53 2,19 2,51 2,29 2,47 1,58 1,56 1,79
Sai so
0,46 0,45 0,53 0,79 0,54 0,71 0,57 0,6 0,73 0,7 0,72 0,65 0,73 0,8 0,67 0,73 0,95 0,81 0,81 0,54 0.61 0,66
Th-232 (10-'Bq/m')
Ham lUOng
4,97 5,35 4,09 7,29 4,71 3,74 8,54 5,96 2,76 5,2 7,05 8,23 7,12 8,02 9,13 6,64 6,79 8,33 8,51 3,48 11,42 6,67
Sai so
0,64 0,97 0,54 1,16 0,59 0,59 1,04 0,85 0,3 0,9
1 1,11 0,93 1,03 1,18 0,84 0,91 1,12 1,42 0,57 0,65 0,71
K-40 (10*Bq/m')
Ham luong
1,47 1,53 1,25 1,16 1,73 2,25
2
2,02 1,05 2,06 2,33 1,98
2
2,16 2,13 3,1 3,28 3,06 2,41 2,06 1,76 2,59
Sal so
0,25 0,27 0,22 0,21 0,3 0,54 0,34 0,35 0,41 0,34 0,43 0,33 0,34 0,37 0,37
0,52
0,57 0,51 0,41 0,22 0,3 0,24
Cs-137 (10-'Bq/m')
-(-; Du&i giai han phat hien)
Bang 2: Ham iMng trung binh cac dong vi phong xa trong khong khi
theo mua tai cac vj tri quan trie khac nhau
Noi lay mau
SdTNMT
TTHN
TTYT T Phu
KCN T Binh
Tram VNCHN
[1]
Miia
Mua
Kho
Mua
Kho
Mua
Kho
Mua
Kho
Mua
Kho
Ham lUOng bui (10''g/m')
1,810 2,130 1,300 1,530 2,070 2,530 1,930 2,160
X
X
Ham
K-40 (10-''Bq/m5) 1,42 1,81 1,81 2,14 1,45 2,91 2,09 2,61 0,48 0,66
luong phong xa
Th-232 (10-'Bq/m') 4,80 7,79 5,00 7,19 6,00 7,88 6,08 7,88 1,92 3,82
U-238 (10-'Bq/m^) 1,43 2,16 1,09 1,64 1,78 2,42 1,68 1,86 0,60 0,75
(- • Dudi gidl han phat hien, X: khong co so lieu)
ciia Trung tam Hat nhan TP HCM dupe thie't ke dat tai Phdng An toan BUc xa va Mdi trudng tU nam 1996 He may dupe trang bj Detectd Germanium sieu tinh khiet (HPGe) model GC1518 ciia hang Canberra eua My, ed cac dae trung ky thuat:
- Hieu suat tUdng ddi: 15%
- Op phan giai nang lupng: 1,8 keV tai dinh 1332 keV(Co-60)
- TT sd dinh/compton: 45/1 tai dinh
1332 keV (Co-60)
- The tfch detectd: 71,1cm' (dudng kfnh 5,34 em va chilu cao 3,20 cm)
III KET QUA, THAO LUAN
De danh gia hien trang ham lupng cac ddng vj phdng xa trong khdng khf, tac gia so sanh ket qua phan tfch tir cac miu thu thap eiia Sd TN va MT TR HCM
11/2010 BAO HO LAO DONG 15
Trang 4H i n i l i C v u g l -2.'8 110"" BViir"]
TC^ \: a.I-l x 10- Dq/ii
• Mtii) niirn
— [ — 1 — —
n n
S6' Si> TTHN TTHN TTYT TTYT hCN KCN Trsm Tr^m
TNMT TNlvAT TPhu TPhu TBinh TBInh VNCHN VNCHN
Do thi 1: Ham li/dng K-40 trung binh theo mua tai cac vi tri
quan trac khac nhau
8.00
-4 0 0
2.00
H A 11 l l
i l O
V i i g T l i - 1
" B q / l l l ' l
3 2
'T
St/ So TTHN TTHN TTYT TTYT KCN KCN T r i i m T r ? n i
TNMT TNMT TPhu T P h d T B i n h T B i n h VNCHN VNCHN
W i g
Do thj 2: Ham lifting Th-232 trung binh theo mua tai cac vi tri
quan trac khac nhau
Hiini liioiig V-liS
(lO'-'BVi""'!
TC\.\; S.14\ 10- Bfi/nt'
I -Mun ii.-iiit;
I I Mii.T iiitrn
— 1 — 1 —
n n
Si- S *
TNMT TN^^^
TTHN TTHN TTYT TTYT KCN KCN Trgm Trsm
, TPhO TPhu TBInh TBinh VNCHN VNCHN
Bo thi 3: Ham lifting U-238 trung binh theo miia tai cac vj tri
quan trie khac nhau
(xem Bang 1) vdi cac ket qua quan trac roi lang phdng xa toan eau tai TR HCM
nam 2006 eua Vien Nghien eiru Hat nhan (Tram VNCHN) [5] Ddng thdi tac gia
so sanh cac ket qua phan tfch vdi TCVN v l ham lupng cho phep ciia cac ddng
vj^phdng xa nay trong khdng khf [4] de danh gia mUc dp nguy hai eua chiing
ddi vdi sire khde con ngudi
TCrcac sd lieu do dac taing binh eiia miu {^mz neu trong Bang 1) va ke't qua
quan trac rd lang phdng xa toan cau tai TR HCM nam 2006 cua Vien Nghien eiru
H^t nhan [5], chiing tdi da thdng ke sd lieu theo tUng mua cho timg vj trf quan trac
de danh gia su khac nhau v l ham lupng cac ddng vj phdng xa eiia eae mau bui khf
(xem Bang 2), sd lieu da dupe bieu diln dudi dang dd thj 1,2 va 3
Ket qua phan tfch ham lupng phdng xa trong cac miu bui khf dupe thu thap
tai eae vj trf quan tam ndi tren theo tirng quan dupe trinh bay trong Bang 1
^ ^ Tap chi /
TU eae do thi 1, 2 va 3 ta cd the riit ra mot sd nhan xet nhu sau:
- Cac ddng vj phdng xa tu nhien K-40, Th-232 va U-238 trong eae mau thu thap eung mdt mua, vdi cac
vj trf lay mau khac nhau cd su chenh lech Dilu nay la do ham lupng bui tai cac vj trf lay mau khac nhau khdng gidng nhau, tuy nhien su chenh lech nay khdng dang ke Rieng ham lupng eiia ddng vi phdng xa nhan tao Cs-137 rat thap nam dudi mire phat hien ciia may
- Ham lupng cac ddng vj phdng
xa tu nhien cd trong mau bui khf tac gia da thu thap deu cao hdn so vdi miu CLia tram quan trac dat tai TR HCM cua Vien Nghien ciru Hat nhan dat d
dp cao tfnh tU mat da't la 25m, vdi 2 dp cao lay mau khac nhau thi ham lupng bui se khac nhau, vj trf lay mau sat mat dat se cd ham lupng bui cao han nen ham lupng eae ddng vj phdng xa trong mau eung cao han
- Hoat dp eiia cac nguyen td phdng xa thu dupe trong qua trinh quan trac khdng khf diu thap han gia trj ndng dp gidi han nen chua gay nguy hai den mdi trudng va eon ngudi
IV.DANHGIAANHHaOTNGCUA TOC DO 0 0 THj HOA TOTI HAM LirOTNG CAC CHAT PHONG XA TRONG TirONG LAI
TR HCM vdi sd lupng dan cu ngay cang tang do qua trinh dd thj hoa, CNH da thu hut mdt luc lupng ngudi nhap eu kha Idn vao TR Dan sd eua TRHCM (theo thdng ke cua trang web
- Bach khoa toan thu 28/12/2007) la 7,163 trieu ngudi, do la chua ke hang tram ngan ngudi vang lai hoac chua dupe thdng ke do khdng khai bao tam trii tai cac dja phuong Tdc dp dd thj hoa ngay cang tang vdi eae khu dan
cu, khu cdng nghiep, eae NM, XN, cd
sd SX ngay cang tang keo theo viec tang dang ke nhu eau di lai ciia cdng ddng Do cac phuong tien cdng cdng
Trang 5KHOA HOC, CONG NGHE - CHUYEN GIAO
chua dap Ung dupe nhu cau nay nen eae phuong tien giao
thdng ca nhan ngay cang tang dang la mot ap lue rat Idn
eho giao thdng van tai Sd lieu thd'ng ke mdi nha't (6/2006)
eho tha'y TRHCM hien cd 3.228.288 xe may, 344.836 xe d
td, trung binh hang thang cd them 37.790 xe may va 960
xe d td dang ky mdi cho tha'y mUc dp gia tang dang ke ciia
cac loai phuong tien nay Cac sd lieu tren cho tha'y ndng
dp bui va cac chat phdng xa trong khdng khf se ngay cang
tang do td'c dp dd thj hoa, cdng nghiep hoa ngay cang
phat then TU dd eho tha'y mUe dp anh hudng ciia chiing
tdi mdi trudng se tang len Day la mdt van d l rat Idn va
phUe tap, chung tdi se d l cap d bai bao khac khi ed dilu
kien
V MOT SO BIEN PHAP GIAM THIEU HAM Ll/ONG
CAC CHAT PHONG XA TRONG TlTONG LAI
De ed cd sd de xua't cac bien phap cu the nham giam
thieu mUe dp d nhiem do eae chat phdng xa va chi trong
tudng lai, nhdm tac gia xin d l xuat cac bien phap trudc mat
nhu sau:
1 Can phai xay dung mang ludi cac tram quan trac
phdng xa trong khdng khf ed djnh (quan trac roi lang phdng
xa toan eau) va di ddng (quan trac phdng xa xung quanh
cac ngudn phat thai cue bd) tai nhilu diem khac nhau tren
dien rdng tai nhilu diem "nhay cam" khac nhau tren dja
ban TR HCM; tU dd ed cd sd de danh gia mdt each chfnh
xac va day dii nha't v l hien trang d nhilm do eae chat
phdng xa tai TR HCM hien nay;
2 Quy hoach, sap xep hoac han che dau tu cac ca sd
SX phat sinh cac chat d nhilm phdng xa hpp ly nham giam
thieu ndng dp eae chat phdng xa trong khdng khf;
3 Phat trien giao thdng cdng cdng, han che eae
phUdng tien ea nhan nham giam thieu ket xe, dap Ung nhu
eau di lai eiia ngudi dan gdp phan giam thieu phat thai cac
chat d nhilm;
4 Dau tukinh phf thfch hpp phuc vu eho cac hoat ddng
kiem tra, giam sat, danh gia cac ngudn d nhiem neu tren
VI KET LOAN VA KIEN NGHj
VI.1 Ket luan
Qua qua trinh nghien ciru, chung tdi da dua ra mdt sd
nhan djnh ve nhUng van d l lien quan den ham lupng cac
ddng vi trong khdng khf tai TR HCM:
- Hien trang v l d nhiim phdng xa trong khdng khf:
nhin chung hoat dp ciia cac nguyen td phdng xa thu
dupe trong qua trinh quan trac khdng khf diu tha'p hon
gia trj ndng dp gidi han Tuy nhien, ham lupng eae chat
nay tang khi ham lupng bui tang, dieu nay eho tha'y rat rd
khi tac gia dd'i chieu so sanh ke't qua phan tfch giUa mua
khd va mua mua
- Hien trang cdng tac giam sat ham lupng ehi va cac ddng vj phdng xa trong khdng khf chua dupe quan tam dau tu dung mUc, dae biet la viec giam sat ham lupng cac ddng vj phdng xa Tai TR HCM chi' cd mdt tram quan trac roi lang phdng xa toan eau (dat d dp cao 25m so vdi mat dat), trong khi dd ham lupng phdng xa tu nhien trong Idp khdng khf ma eon ngudi thudng xuyen sinh sd'ng (tU be mat da't den dp eao khoang 3m) dang bi xao trdn va tang len dang ke do qua trinh dd thj hda lai chua cd tram quan trac nao dupe xay dung
- De cd Cd sd de xua't cac bien phap eu the nham giam thieu mUe dp P nhiem do cac chat phdng xa va chi trong tUdng lai, can thie't phai thue hien ddng bp eae giai phap
da neu d tren, tU dd ed nhffng djnh hudng chie'n lupe va dau tu phu hpp nham giam thieu anh hudng xau den mdi trudng trong tuong lai
VI.2 Kien nghj Nhdm tac gia rat mong mud'n tie'p tuc eae nghien cUu tilp theo tren dja ban toan TR HCM De nghj cac cd quan quan ly nha nude tao dilu kien de nhdm nghien cUu cd the thuc hien nghien cUu eiia minh
Tai lieu tiiam idiao
Tieng Viet
[1] Ngo Quang Huy, Tran Van Luyen, Nguyin Van Mai (1999), Khao sat nen phong phong xa mdi trudng doi vdi mgt so doi tugng moi trudng tai TP HCM, Hgi nghi Vat ly va Ky thuat Hat nhan lan thir 3, Da Lat
[2] Nguyen Van Mai (2003), Phan tich, danh gia va kien nghi mgt tieu chuan quoc gia ve ham lugng phdng xa Cs-134, Cs-137, Th-232, U-238, K-40 trong cac mau gao xuat khau chinh eua khu vuc dong bang song CO'u Long, Bao cao de tai ca sa, Vien Nang lugng Nguyen tir Viet Nam, Ho Chi Minh
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