Exposició laboral a compostos orgànics i metalls en la planta incineradora de residus especials del Camp de Tarragona. (2003)

In recent years, incineration has demonstrated to be a commercially available technology for hazardous waste disposal. According to the assessments done to date, there appears to be little human risk from hazardous waste incinerator (HWI) emissions.
The objective of this study was to determine and to compare blood and urine concentrations of a number of organic compounds in workers at a hazardous waste incinerator (HWI) of Tarragona, before one and two years after working in the plant, and to assess if the incinerator can be a risk for their health. Twenty-eight workers of the new HWI were selected to test internal exposure to organic substances. Twenty-two men and 6 women between 23 and 58 years, who had not been previously exposed to these substances, were included in the study. They were divided into three groups according to the workplace and task: group I, incinerator operators, boiler maintenance, control panel, furnace maintenance and waste gas washing operators; group II, laboratory workers, and group III, management and office workers.
In all samples, the concentrations of benzene, toluene, ethiylbenzene and m-xylene were under the respective detection limit (1 mg/L for benzene and 4 mg/L for the other compounds). The mean levels in plasma of the HWI workers during the three years of study (1999, 2000 and 2001) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were 27.6, 16.9 and 10.0 ng I-TEQ/kg lipid, respectively (significant differences were found respect to 2001). The mean levels of hexachlorobenzene (HCB) were 152, 115.4 and 181.7 mg/kg lipid, respectively. Respect to polychlorinated biphenyls (PCB 28, 52, 101, 138, 153 and 180) the mean levels in the year 1999 were 18.5, 10.4, 9.0, 151, 213 and 209 mg/kg lipid, respectively. In the year 2000, were 2.2, 1.3, 2.0, 89.0, 125.4 and 121.7 mg/kg lipid. Finally, in 2001, the mean levels were 3.4, 1.5, 2.0, 74.0, 103.8 and 92.0 mg/kg lipid.
The urinary excretion of (CLPs) can be used as an indirect indicator of current exposure to PCDD/Fs, whereas the urinary levels of 1-HP were determined as an indicator of exposure to PAHs. The mean urinary levels during the three years of study of 2,4- dichlorophenol (DCPs) were 1.4, 4.4, 4.7 mg/g creatinine, respectively. For 2,5-dichlorophenol (DCPs), were 5.52, 110.1, 123.1 mg/g creatinine, respectively. For 2,4,5- trichlorophenol (TCPs) were 0.3, 0.6, 0.4 mg/g creatinine, and for 2,4,6-trichlorophenol (TCPs) were 0.3, 2.0, 0.9 mg/g creatinine, respectively. Finally, for pentaclorfenol (PCP) were 0.3, 1.8, 1.0 mg/g creatinine. Significant differences (p<0.05) were noted for 2,5-chlorophenol (DCPs) and pentachlorophenol (PCP). 1-HP could be only detected in few samples, the others samples were under the detection limit (0.1 µg/L). Although the present results showed a notable variability for the levels of chlorophenols, median values of these compounds were similar or even lower than those considered as potential reference values.
The blood levels of manganese were 12.5, 5.9 and 10.9 mg/L (1999, 2000 and 2001, respectively). Significant differences (p<0.01) were noted between the years 2000 and 2001. The mean levels of lead were 3.4, 3.5 and 3.0 mg/dL, respectively. The levels of mercury in 1999 and 2001, were under the detection limit, but in 2000 the mean level was 9.9 mg/L.
The urinary mean levels of arsenic, in the periode 1999-2001, were 54.8, 1.45 and 1.35 mg/g de creatinine, respectively. The levels of cadmium were 0.35, 0.40 and 0.21 mg/g de creatinine, respectively. Significant differences (p<0.01) were noted in 2001. Chromium levels were 0.14 and 0.30 mg/g de creatinine (1999 and 2000, respectively). In 2001, the levels were under the detection limit. Nickel mean levels during the three years of study were 11.6, 3.36 and 3.63 mg/g de creatinine, respectively.
On the other hand, the concentrations of beryllium and vanadium were under their detection limits in all samples (4 mg/l and 16.6 mg/L, respectively) during the three years of study.
According to the results of the current survey, one year of potential exposure to the organic and inorganic substances here analyzed would not mean any specific health problem for the workers at the HWI. Future surveys will be performed in order to detect potential health risks with time for these workers.
RESUM
Lactual desenvolupament industrial ha portat com a consequencia laugment del residus toxics i perillosos els quals no poden ser reciclats, reduits o dipositats en llocs segurs. Aixo, ha conduit a la construccio dincineradores, basades en un proces doxidacio termal, on els residus es converteixen en gasos i residus solids incombustibles.
El proposit daquest estudi ha sigut el dobtenir dades de referencia (abans de que la planta funciones), aixi com controlar durant 2 anys els nivells duna serie de compostos organics i metalls pesants en els treballadors de la Incineradora de Residus Especials del Camp de Tarragona. Escollint-se un total de 28 treballadors distribuits en operadors de planta, laboratori, i administracio (6 dones i 22 homes).
Els valors obtinguts en plasma sanguini al 1999, 2000 i 2001, pels dibenzodioxines i dibenzofurans policlorats (PCDD/Fs) han sigut duna mitjana de 27.6, 16.9 i 10.0 ng I-TEQ/kg de lipid, respectivament (mostrant un descens estadisticament significatiu). Pels nivells hexaclorbenze (HCB) shan obtingut una mitjana de 152, 115.4 i 181.7 mg/kg lipid, respectivament. Respecte als PCBs, pels congeneres 28, 52, 101, 138, 153 i 180, lany 1999 els valors de les mitjanes han estat de 18.5, 10.4, 9.0, 151, 213 i 209 mg/kg de lipid, respectivament. Per lany 2000, han estat de 2.2, 1.3, 2.0, 89.0, 125.4 i 121.7 mg/kg lipid. Finalment, per lany 2001, s'han trobat unes mitjanes de 3.4, 1.5, 2.0, 74.0, 103.8 i 92.0 mg/kg lipid. Els nivells de BTEX (benze, tolue, etlibenze i m-xile) en sang total han estat per sota del limit de deteccio (1mg/L pel benze i 4 mg/L per la resta).
Referent als compostos organics en orina, les concentraciones medianes del clorfenols han estat pels anys 1999, 2000 i 2001, respectivament, de 1.4, 4.4, 4.7 mg/g creatinina pel 2,4-clorfenol, 5.52, 110.1, 123.1 mg/g creatinina pel 2,5-clorfenol, 0.3, 0.6, 0.4 mg/g creatinina pel 2,4,5-triclorfenol, 0.3, 2.0, 0.9 mg/g creatinina pel 2,4,6-triclorfenol, i 0.3, 1.8, 1.0 mg/g creatinina pel pentaclorfenol La majoria de nivells de l1-hidroxipire han estat sota el limit de deteccio (0.1mg/L). El 2,5-diclorfenol, i el PCP van mostrar nivells significativament superiors en els dos ultims estudis que els observats al realitzat lany 1999 (blanc). Malgrat tot, els valors es poden considerar com a normals.
Respecte als metalls en sangs, els valors mediana de manganes va ser de 12.5, 5.9 i 10.9 mg/L (1999, 2000 i 2001, respectivament). Sent les diferencies estadisticament significatives (p<0.01) entre lany 2000 i 2001. Pel plom, els valors mediana obtinguts van ser de 3.4, 3.5 i 3.0 mg/dL (1999, 2000 i 2001, respectivament). Respecte al mercuri, els anys 1999 i 2001, els seus nivells van estar per sota del limit de deteccio, mentre que lany 2000 es va obtenir un valor mediana de 9.9 mg/L. Altrament, el beril·li es va mantenir per sota del limit de deteccio durant els 3 anys destudi.
En orina, els anys 1999, 2000 i 2001, els nivells mediana darsenic, van ser de 54.8, 1.45 i 1.35 mg/g de creatinina, respectivament. Pel cadmi, els valors de mediana van ser de 0.35, 0.40 i 0.21 mg/g de creatinina, respectivament. Hi ha una disminucio lany 2001 sent estadisticament significativa (p<0.01). Pel crom, 0.14 i 0.30 mg/g de creatinina son els valors mediana (1999 i 2000, respectivament). En lestudi de lany 2001, es van obtenir nivells inferiors al limit de deteccio. El niquel va variar durant els 3 anys d'estudi (1999, 2000 i 2001) amb valors mediana de 11.6, 3.36 i 3.63 mg/g de creatinina, respectivament. Per ultim, els nivells de vanadi no van estar detectats en la seva majoria (limit de deteccio: 16.6 mg/L). En lestudi realitzat lany 2001, es va observar un valor mediana de 15.1 mg/g de creatinina (23.5 mg/L).
En termes generals, les xifres corresponents al blanc (1999) i als 2 anys de potencial exposicio (2000 i 2001) a compostos organics i metalls pesants en els treballadors de la incineradora de residus especials del Camp de Tarragona, es poden considerar com a normals, amb referencia a les d'una poblacio no exposada ocupacionalment. No hi ha hagut cap aportacio significativa que sigui especifica de risc laboral a la planta incineradora.