Water pollution in Elefsina

Sofia KoukouraNatalia Bolou

Philip Siaplaouras

Purposes & Goals

To determine the quality of the Elefsina's sea water

Identify the sources of pollutionCompare industrial & residental

pollutionTo conclude to some results regarding

the data collected

HypothesisAt the beginning we thought that the sea near to an industrial area (Elefsina) would be much more polluted than the sea in the residential area. More specifically about Aspropirgos, we thought that we would find there certain elements that could prove the existence of pollution and eutrofication.

Eutrofication: is caused by the continuous enrichment of the water with nutrients. The presence of these essential nutrients causes the exponential increase of plants and the distraction of the ecological balance

Sources of pollution in Elefsina

Landfill of Ano

Liosia

Sea transports

Industrial units

Design of our research

The pupils are divided in 4 teams, 2 for the industrial areas and 2 for non-industrial.

All teams travelled to get water samples from two distinct parts of Elefsina bay (Aspropyrgos for industrial areas and

Loutropyrgos for non-industrial)

We began with filtering the samples in preweighted

filters2L from Aspropyrgos' sample2L from Loutropyrgos sample

The filters which kept the air particles were left for one week in a drier with the

aim of keeping away the water. By removing the mass of the filters we would

find the mass ofthe air particles.

Air Particles

Suspended particles (Results)

9,0Loutropyrgos

9,5Aspropyrgos

Air Particles (mg/L)Sample

NO2-

In order to determine the quantity of the

NO2- we followed the forthcoming

procedure:

40ml of filtered sample + 5ml of solution

A (we waited for 5min) + 5ml of solution

B (we waited for 10min) and we

measured the absorption of singly

frequenced light from the final (coloured)

product.

In order to get some useful results from the

measured absorbation ratios we had to give

the computer some absorbation values from

solutions with known concentrations. After

“feeding” the machine with these values we

could easily compute the concentration using

simple mathematical functions.

0,28630,3

0,15720,2

0,09220,1

AbsorptionConcentration in NO2

-

A= 0,4726 c + 0,0525

Measurement 2: 0,0541

0,0556Measurement 1: 0,0571

Loutropyrgos

Measurement 2: 0,0526

0,0536Measurement 1: 0,0546

Aspropyrgos

Average absorption

AbsorptionSample

Results (NO2-)

0,0065Loutropyrgos

0,0023Aspropyrgos

C (μgions/L)Sample

Chlorophyll

We had strained in two filters• 2L from Aspropyrgos sample• 2L from Loutropyrgos sample.These filters were put into centrifugal pipes and

were contemplated with acetone. The centrifugal procedure followed and after that the measurement of the absorption of the light.

Firstly, the absorption measurements were carried out in the plain samples and then we measured again after adding 8 drops of solution HCl.

By using a mathematical equation we were able to find the concentration of chlorophyll in the samples.

Aspropyrgos sample

0,84800,7605750nm

0,97300,8460665nm

Absorption

Aa “sample’s + HCl”

Absorption

A0 “sample’s”

Wave length

Loutropyrgos sample

0,46630,4988750nm

0,48770,5402665nm

Absorption

Aa “sample’s + HCl”

Absorption

A0 “sample’s”

Wave length

Chlorophyll results

0,4272Loutropyrgos

0,8437Aspropyrgos

Concentration (μg/L)Sample

C chlorophyll-a = 26,7 ·| E6650 – E665

a |·8

V·5

CONCLUSION

• Aspropyrgos' waters, despite being in an industrial area, has a lower concentration in NO2

-

• Aspropyrgos' waters have slightly more air particles. This small difference is not analogous to the tremendously different environment. Thus, the concentration of air particles cannot be used as an evidence of pollution

• Although Aspropyrgos' waters have a larger concentration in Chlorophyl, this is not due to eutrofication, as originally thought.

ProposalsProhibition of factory wasteControl over the use of chemical

fertilizersControl over the naval waste thrown

into the gulf