Heavy Metal Heavy Metal Concentrations in Concentrations in Tyler Run Creek Tyler Run Creek

Water and SedimentWater and SedimentOlivia Yaple and Sara WingOlivia Yaple and Sara Wing

BackgroundBackground

Water and sediment contamination Water and sediment contamination is important to study due to its is important to study due to its potential adverse affects on public potential adverse affects on public water supply quality and aquatic water supply quality and aquatic lifelife11

Cd in particular can permeate Cd in particular can permeate calcium channels of aquatic calcium channels of aquatic vegetation and disrupt the plant vegetation and disrupt the plant water statuswater status22

Background, Cont.Background, Cont.

Cd, Pb, Cu, and Zn are heavy Cd, Pb, Cu, and Zn are heavy metals commonly found in water metals commonly found in water and sediment samples that can and sediment samples that can reach toxic levelsreach toxic levels33

These heavy metals can These heavy metals can precipitate in an aquatic system precipitate in an aquatic system and deposit in sediment, or end and deposit in sediment, or end up there via sedimentationup there via sedimentation44

Background, Cont.Background, Cont.ICP and AA are both used to ICP and AA are both used to determine metal concentrations in determine metal concentrations in aqueous solutionsaqueous solutions

EPA freshwater quality EPA freshwater quality recommendations:recommendations:55

MetalConcentration Limit

(ppm)

Cd 0.002

Pb 0.065

Cu 0.00145

Zn 0.120

HypothesesHypothesesWater from farther downstream would Water from farther downstream would have higher concentrations of all metals have higher concentrations of all metals while farther upstream would have while farther upstream would have lower concentrations. lower concentrations.

Sediment from farther downstream Sediment from farther downstream would have higher metal concentrations would have higher metal concentrations than farther upstreamthan farther upstream

Sediment metal concentrations would be Sediment metal concentrations would be higher than water metal concentrations.higher than water metal concentrations.

MethodMethodWater samples were collected from Tyler Water samples were collected from Tyler Run creek at 10 foot and 50 foot increments Run creek at 10 foot and 50 foot increments upstream and downstream of the fordupstream and downstream of the ford

Sediment samples were collected from the Sediment samples were collected from the same area and extractedsame area and extracted

Samples were analyzed using ICP and AASamples were analyzed using ICP and AA

Extraction MethodExtraction MethodA funnel filled with filter paper was A funnel filled with filter paper was filled with 1.5 cm of sediment and let filled with 1.5 cm of sediment and let sit until drysit until dry

The dry sample was washed twice The dry sample was washed twice with 5 ml quantities of 0.1M HNO₃ and with 5 ml quantities of 0.1M HNO₃ and let dry after each wash. The filtrate let dry after each wash. The filtrate was collected in 100 ml volumetric was collected in 100 ml volumetric flasksflasks

The filtrate was diluted to 100 ml The filtrate was diluted to 100 ml using deionized water therefore all using deionized water therefore all found concentrations were 10 times found concentrations were 10 times less than actual concentrationless than actual concentration

StandardsStandards5 ppm, 10 ppm, 15 ppm, and 20 ppm 5 ppm, 10 ppm, 15 ppm, and 20 ppm standards of Cd, Pb, Cu, and Zn were standards of Cd, Pb, Cu, and Zn were prepared via the following dilution prepared via the following dilution method:method:

10 ppm = 10 ppm = 1 ml of 1000 ppm stock 1 ml of 1000 ppm stock solutionsolution

100 ml DI water100 ml DI water

• ICP used standards containing all metals• AA used separate standards for each metal

Method, ContinuedMethod, ContinuedFor both instruments, the run order For both instruments, the run order was:was:

1) Blank2) 5ppm standard3) 10ppm standard4) 15ppm standard5) 20ppm standard6) Water 50 ft downstream7) Water 10 ft downstream8) Water 10 ft upstream9) Water 50 ft upstream

10) Sediment 50 ft downstream11) Sediment 10 ft downstream12) Sediment 10 ft upstream13) Sediment 50 ft upstream14) Spiked sample

Proving the MethodProving the MethodUsing the spiked samples’ results, Using the spiked samples’ results, the method was provedthe method was proved

For ICP, the sample of 10 ft For ICP, the sample of 10 ft downstream water was spiked with downstream water was spiked with 25 ppm Pb. The results showed 25 ppm Pb. The results showed 24.253 ppm.24.253 ppm.

24.253 ppm24.253 ppm x 100 % = 97.012 % x 100 % = 97.012 % recoveryrecovery

25 ppm25 ppm

Proving the Method, Proving the Method, Cont.Cont.• For AA:For AA:

Sample Used

Spike Conc.

Resulting Conc.

Calculation

Percent Recovery

Cd10 ft

upstream water

20 ppm 19.45 ppm

(Resulting/Spiked Conc.)

x 100%97.25

Pb10 ft

downstream water

25 ppm 22.66 ppm

(Resulting/Spiked Conc.)

x 100% 90.64

Cu10 ft

downstream water

20 ppm 21.41 ppm

(Resulting/Spiked Conc.)

x 100%107.05

Zn50 ft

downstream water

20 ppm 18.14 ppm

(Resulting/Spiked Conc.)

x 100% 90.70

Proving the Method, Proving the Method, Cont.Cont.

Based on the high percent recoveries Based on the high percent recoveries for both ICP and AA, we postulate for both ICP and AA, we postulate that both instruments were detecting that both instruments were detecting all four metal concentrations, though all four metal concentrations, though the AA could not detect the metal the AA could not detect the metal concentrations in the samplesconcentrations in the samples

Therefore, all results reported are Therefore, all results reported are based on ICP databased on ICP data

ResultsResults

SampleCd

Concentration (ppm)

Pb Concentrat

ion(ppm)

Cu Concentration (ppm)

Zn Concentration (ppm)

Water 50 ft downstream

0.0723* 0.0624 0.3144* 0.0836

Water 10 ft downstream

0.0245* 0.0458 -0.0109 0.0247

Water 10 ft upstream

0.01104* 0.3175* -0.0193 0.0078

Water 50 ft upstream

0.0055* 0.0373 -0.0198 0.00033

Sediment 50 ft

downstream0.662* 0.671* 0.234* 0.572*

Sediment 10 ft

downstream0.290* 1.5593* 0.895* 0.269*

Sediment 10 ft upstream

0.089* 1.3310* 0.143* 0.254*

Sediment 50 ft upstream

0.044* 0.651* -0.061 0.076*denotes a metal concentration in excess of the EPA recommended limits

ConclusionsConclusionsResults showed that sediment samples Results showed that sediment samples overall had much higher Cd, Pb, Cu, overall had much higher Cd, Pb, Cu, and Zn concentrations than water and Zn concentrations than water samplessamples

For sediment samples, farther For sediment samples, farther downstream samples had the highest downstream samples had the highest metal concentrationsmetal concentrations

For water samples, Cd had the highest For water samples, Cd had the highest concentrations downstream, Zn concentrations downstream, Zn showed the same pattern, but was not showed the same pattern, but was not over the EPA limit. over the EPA limit.

DiscussionDiscussionICP Cu data provided some negative ICP Cu data provided some negative values, these are explained by the values, these are explained by the Cu concentrations being below the Cu concentrations being below the detectable limit of 0.002 ppmdetectable limit of 0.002 ppm55

Possible sources of error include but Possible sources of error include but are not limited to: are not limited to:

skewed calibration curvesskewed calibration curves

Non-standardized sample Non-standardized sample procurementprocurement

Many samples contained heavy metal Many samples contained heavy metal concentrations close to the detection concentrations close to the detection limit limit

ReferencesReferences11Saygi, Y.; Yiğit, S. A. Saygi, Y.; Yiğit, S. A. Heavy metal concentrations in Heavy metal concentrations in Yeniçağa Lake and its potential sources: Soil, water, Yeniçağa Lake and its potential sources: Soil, water, sediment, and plankton. sediment, and plankton. Environ. Monit. Assess. Environ. Monit. Assess. 20122012, , 184184, 1379-1389., 1379-1389.

22Perfus-Barbeoch, C.; Leonhardt, N.; Vavasseur, A.; Perfus-Barbeoch, C.; Leonhardt, N.; Vavasseur, A.; Forestier, C. Forestier, C. Heavy metal toxicity: Cadmium Heavy metal toxicity: Cadmium permeates through calcium channels and distrubs permeates through calcium channels and distrubs the plant water status. the plant water status. Plan. Jour.Plan. Jour. 2002 2002, , 3232(4), 539-548.(4), 539-548.

33Filgueiras, A. V.; Lavilla, I.; Bendocho, C. Filgueiras, A. V.; Lavilla, I.; Bendocho, C. Chemical Chemical sequential extractions for metal partitioning in sequential extractions for metal partitioning in environmental solid samples. environmental solid samples. J. Environ. Monit. J. Environ. Monit. 20022002, , 44, , 823-857.823-857.

44Avil-Peréz, P.; Balcázar, M.; Zarazia-Ortega, G.; Barceló-Avil-Peréz, P.; Balcázar, M.; Zarazia-Ortega, G.; Barceló-Quintal, I.; Díaz-Delgado, C. Quintal, I.; Díaz-Delgado, C. Heavy metal concentrations Heavy metal concentrations in water and bottom sediments of a Mexican in water and bottom sediments of a Mexican reservoir. reservoir. Sci. of the Tot. Environ. Sci. of the Tot. Environ. 19991999, , 234234(1-3), 185-(1-3), 185-196.196.

55United State Environmental Protection Agency. National United State Environmental Protection Agency. National Recommended Water Quality Criteria. Recommended Water Quality Criteria. http://water.epa.gov/scitech/swquidance/standards/current/http://water.epa.gov/scitech/swquidance/standards/current/index.cfm (accessed April 25, 2012).index.cfm (accessed April 25, 2012).