THE FLUSHING FOR LEAD IN FRESHWATER SNAIL FILOPALUDINA JAVANICA

Increasing industrial activities in Lamongan District is assumed to be followed by the increase on the amount of liters in rivers and ponds. Freshwater snails (Filopaludina javanika v.d Busch 1844) that live in rivers and ponds are always exposed to heavy metals. Based on the result of the measurement of Pb in freshwater snails in Waung river, Glagah subdistrict, Lamongan, the highest amount of Pb reached 4.48 mg/kg. This aim of this research was to decrease the amount of Pb in freshwater snails. This research employed an experimental method using complete randomized design with 4 treatments and 3 repetitions; P1 (6-hour flushing procedure), P2 (12-hour flushing procedure), P3 (18-hour flushing procedure), and P4 (24-hour flushing procedure) with the reduction on the level of Pb in the “whole organ” of the freshwater snails. The results show that 24-hour of flushing has reduced the amount of Pb as much as 53.2%, from 2.65 ppm, leaving only 1.24 ppm. Meanwhile, the least reduction was found in the 6-hour flushing procedure at 7.2%. The results of the treatments have obtained amount of Pb under the minimum safety requirement set by BPOM (2009), Fisheries (DKP) No: Kep 17/Men/2004, SK Ditjen POM No. 03725/B/SK/VII/1989, in which it is stated that materials that contain heavy metals less than 1.5 ppm are safe to consume for duck weft and for human. Further researchers are suggested to investigate the accumulation of lead (Pb) in ducks that consume freshwater snails within certain period of time.

bodies.Therefore, it was necessary to find out the amount of lead in the whole organ of freshwater snails in Glagah subdistrict as an anticipation of its effect on ducks and human that consume the snails.Brite et al., (2006) explained that maintaining the quality and the safety of food products can be done by reducing the amount of Pb in the snails.The amount of Pb can be reduced by conducting flushing procedure or by soaking the snails and flowing them with clean water before they are used as food for poultry and for human (DKP, 2008).In line with this view, Chan et al. (1999) said that flushing off the heavy metals in snails can be done by moving them out from the contaminated habitat to a cleaner habitat.This research provides information on the appropriateness of freshwater snails to use as food for poultry and for human consumption.This research attempted at reducing the amount of Pb in freshwater snails (Filopaludina javanika v.d busch 1844) through flushing procedures.

METHODS OF RESEARCH
Freshwater snails around the size of 25 -27 mm which were usually used as duck welt (Filopaludina javanika v.d busch 1844) were collected from ponds and rivers which were exposed to heavy metals including Pb.The observation and the flushing procedures were conducted in the laboratory around the field.This reseach employed an experiment method using a complete randomized design with 4 treatments and 3 repetitions, including identification on the quality of the water (pH, temperature, DO) and the amount of Pb in the "whole organ" of the snails.The flushing procedure used clean freshwater that did not contain any Pb which was then filled into 12 containers.The flusing procedures used in this study were modified from the procedures performed by Nuriyani in 2016.Nuriyani (2016) showed that the soaking procedure did not give any significant effect without the changing of water.
The sample of freshwater snails used in the flushing procedure contained Pb amount beyond the safety limit set by BSN (1.5 mg/kg), DKP (1.5 mg/kg) Regulation of Food Specification NO 466/2001/EC (0.1 ppm) and Depkes (2 mg/kg).Each container was filled with water up to 20 cm for 4 different flushing periods of 6, 12, 18 and 24 hours in 3 repetitions.The flushing speed at 0.43 m/second was used regarding to the suggestions from previous studies by measuring the average water speed in the habitat.This speed was also determined from the previous study conducted by Ahmad (2012) in which the flushing of water at 0.43 m/second in 3 weeks has successfully reduced the amount of Pb in the shell of the snails from 1.19 ppm to 0.45 ppm (62.18%).

RESULTS AND DISCUSSION
The result of the first stage preliminary study done to the flesh of freshwater snail in Waung river showed the highest contamination of lead (Pb) of 4.48 mg/kg, whilst the least amount of lead (Pb) was found in Bengawan Blawi river at 0.5 mg/kg.
The concentration of lead (Pb) in the "whole organ" of the freshwater snails showed the highest value in Station 1 at 3.432 ppm, followed by Station 3 at 2.924 ppm, Station 2 at 2.402 ppm and the lowest one was found in Station 4 at 0.07 ppm (Figure 2).Regarding to the decision letters issued by the Ministry of Marine and Fisheries No: Kep 17/Men/2004 and National Standardization Institution (2009), the maximum limit of lead content is 1.5 ppm.Thus, the freshwater snails collected from station 1, 2, and 3 had reached over the safety limit, and only the ones found in station 4 were under the limit.
In the second preliminary study, the amount of lead (Pb) in station 4 decreased from 4.48 ppm to 0.07 ppm.The decrease was resulted by the increase on the water speed in Waung river from 0.5 m/second to 1 m/second in February until July 2017.The faster water speed has flushed the amount of Pb within the flesh of the snails.Besides, mud litters thrown into the river from rice fields were low since it was not yet the harvest time.In the harvest time, farmers throw away the litters from their field into the river, ca sedimentation in the river which forces freshwater snails to accumulate more Pb in their bodies.According to Purbalisa and Mulyadi (2013) the contamination of lead (Pb) in the rice fields is assumed to come from the phosphate element as the Phosphate fertilizer contains P nutrients such as Ca, Mg and other micro elements including Fe, Mn, Cu, Zn and some heavy metals at various amount such as Cd (0.1 ppm), (Setyorini,2003).Results of Flushing Procedure concluded that the longer the flushing time, the higher the amount of ions flushed away from the flesh of the snails, which results to lower concentration of Pb in the snails.6 process has decreased the concentration of Pb as much as 7.2%.The 12 process has decreased 19.6% of the Pb, leaving only 1.12 ppm.The 18 process has decreased 38.1% of the Pb concentration, remaining only highest decrease of Pb was obtained from the 24 successfully decreased 53.2% of Pb concentration from 2.65 ppm to 1.24 ppm. the maximum limit of Pb concentration determined by the BPOM (2009) at 1.5 ppm, the concentration of Pb in freshwater snails after the flushing process is under th safe for human consumption.
Suprijanto et al. (1997) stated that depuration procedure decreases Pb concentration within the organisms' bodies since there is no addition of heavy metals decreased concentration of Pb s resulted form the release of metallic ions from the protein structure in the snails which are leached from their flesh as the balancer of Pb concentration in the flesh.Naturally, metallic ion exchange happ bounded to metalloprotein for metalloprotein chains are not stable 2004).
The result of Anova test has resulted an average concentration of Pb after the flushing procedure with a significant highly effective in decreasing the concentration of Pb in freshwater snails.It happened due to the changing of water all the time which washed away the heavy metals in the snails' body.This insight goes in line with Riyadi (2016) who stated that clams are able to release heavy metals from their bodies which are later flushed away by ever flowing water circulation.Zhu et al., (1999) mentioned that the effort to clean clams and snails is often done in land with stable supply of flow-through water.Water Quality.Physical and chemical and during the treatment.Water quality shows the relative condition of the water related to the necessities of creatures living in water.Moreover, the water quality also becomes the standard measurement to determine the quality of wa conducted on site in for each treatment including water temperature, pH and the dissolved oxygen (DO).The average score of the water quality measurement in each flushing process is presented in Table 1.
The average temperature during the flushing treatment was around 26.9 average temperature shows that the water in the containers was favorable for the freshwater snails to live.Sumarni (1989)  Results of Flushing Procedure.Based on the result of this research, it can be concluded that the longer the flushing time, the higher the amount of ions flushed away from the flesh of the snails, which results to lower concentration of Pb in the snails.6 eased the concentration of Pb as much as 7.2%.The 12 process has decreased 19.6% of the Pb, leaving only 1.12 ppm.The 18 process has decreased 38.1% of the Pb concentration, remaining only was obtained from the 24-hour flushing process which has successfully decreased 53.2% of Pb concentration from 2.65 ppm to 1.24 ppm. the maximum limit of Pb concentration determined by the BPOM (2009) at 1.5 ppm, the freshwater snails after the flushing process is under th (1997) stated that depuration procedure decreases Pb concentration within the organisms' bodies since there is no addition of heavy metals decreased concentration of Pb s resulted form the release of metallic ions from the protein structure in the snails which are leached from their flesh as the balancer of Pb concentration Naturally, metallic ion exchange happens easily, especially to ions which are bounded to metalloprotein for metalloprotein chains are not stable (Wahyuni dan Widiyanti, The result of Anova test has resulted an average concentration of Pb after the flushing procedure with a significant effect (p<0.05).Hence, flushing procedure can be regarded highly effective in decreasing the concentration of Pb in freshwater snails.It happened due to the changing of water all the time which washed away the heavy metals in the snails' body.
ne with Riyadi (2016) who stated that clams are able to release heavy metals from their bodies which are later flushed away by ever flowing water circulation.Zhu (1999) mentioned that the effort to clean clams and snails is often done in land with through water.
The Result of AAS Test to the Whole Organ of Freshwater Snails after the Flushing Procedure hysical and chemical parameters of the water were measured before and during the treatment.Water quality shows the relative condition of the water related to the necessities of creatures living in water.Moreover, the water quality also becomes the standard measurement to determine the quality of water ecosystem.Measurement was on site in for each treatment including water temperature, pH and the dissolved oxygen (DO).The average score of the water quality measurement in each flushing process re during the flushing treatment was around 26.9 average temperature shows that the water in the containers was favorable for the freshwater snails to live.Sumarni (1989)  Based on the result of this research, it can be concluded that the longer the flushing time, the higher the amount of ions flushed away from the flesh of the snails, which results to lower concentration of Pb in the snails.6-hour flushing eased the concentration of Pb as much as 7.2%.The 12-hour flushing process has decreased 19.6% of the Pb, leaving only 1.12 ppm.The 18-hour flushing process has decreased 38.1% of the Pb concentration, remaining only 1.64 ppm.The hour flushing process which has successfully decreased 53.2% of Pb concentration from 2.65 ppm to 1.24 ppm.Regarding to the maximum limit of Pb concentration determined by the BPOM (2009) at 1.5 ppm, the freshwater snails after the flushing process is under the limit and is (1997) stated that depuration procedure decreases Pb concentration within the organisms' bodies since there is no addition of heavy metals from outside.The decreased concentration of Pb s resulted form the release of metallic ions from the protein structure in the snails which are leached from their flesh as the balancer of Pb concentration ens easily, especially to ions which are (Wahyuni dan Widiyanti, The result of Anova test has resulted an average concentration of Pb after the flushing 5).Hence, flushing procedure can be regarded highly effective in decreasing the concentration of Pb in freshwater snails.It happened due to the changing of water all the time which washed away the heavy metals in the snails' body.
ne with Riyadi (2016) who stated that clams are able to release heavy metals from their bodies which are later flushed away by ever flowing water circulation.Zhu (1999) mentioned that the effort to clean clams and snails is often done in land with The Result of AAS Test to the Whole Organ of Freshwater Snails after the Flushing were measured before and during the treatment.Water quality shows the relative condition of the water related to the necessities of creatures living in water.Moreover, the water quality also becomes the ter ecosystem.Measurement was on site in for each treatment including water temperature, pH and the dissolved oxygen (DO).The average score of the water quality measurement in each flushing process re during the flushing treatment was around 26.9 -30.5 0 C. The average temperature shows that the water in the containers was favorable for the freshwater snails to live.Sumarni (1989)

Figure 1 -Figure 2 -
Figure 1 -The location of sample collection in the second stage preliminary study subdistrict, Lamongan (Source

Figure 3 -
Figure 3 -The Result of AAS Test to the Whole Organ of Freshwater Snails after the Flushing stated that most Mollusca, especially snails are able to live within the temperature of around 22 Bellamnya javanika family Viviparidae are able to tolerate temperature up to 35 the pH found in each treatment was around 7.
stated that most Mollusca, especially snails are able to live the temperature of around 22 -33 0 C.Meanwhile, Junting (1956) mentioned that family Viviparidae are able to tolerate temperature up to 35 the pH found in each treatment was around 7.3 -7.5.Hynes (1987)explained that usualy stated that most Mollusca, especially snails are able to live C.Meanwhile, Junting (1956) mentioned that family Viviparidae are able to tolerate temperature up to 35 0 C. generally, 7.5.Hynes (1987) explained that usualy