water tests results

SAF(V)E WATER, SWEET LIFE

COMENIUS PROJECT

Water analysis results

On January 2006 students collected water samples and bring them to lab. Water was tested according to several parameters. Each group tested one parameter and made a report.

On May 2006 students collected water samples again, at the same selected water resources. The same groups tested the same parameters.

Water Quality Analysis

Physico-chemical Parameters:

• Calcium

• Hardness

• Dissolved Oxygen

• Sulfides

Microbiological Parameters:

• Coliforms

Undesirable substances Parameters:

• Nitrates

NITRATES (VMA: 50 mg/l)

Fonte dos Canos

Pias A-do-Pinto

January 2006 4,0 4,5 >5

May 2006 >5 >5 >5

The higher results obtained in second tests may be due to agriculture uses and to the increased temperature. The water with nitrates can produce cancer, so it is important to evaluate this parameter.

HARDNESS

Jan2006 May2006

A-do-Pinto 70 mg/l 55 mg/l

Poço do Pedro 150 mg/l

The hardness (calcium carbonate) is a parameter that varies with time and place. The higher the hardness the higher benefits to heart diseases.

CALCIUM (VMR: 100 mg/l)

Tap water Enxoé Vareta Pias Alqueva

May

2006

90/100 70 45 67 63

Calcium is important to bones, but if too much it contributes to lack of other elements. All samples showed higher rates than 40 mg/l.

SULFIDES (VMA: 250 mg/l)

Fonte dos Canos

Pias Vila Nova

January 2006

<1 <1 <1

May

2006

<1 <1 <1

We think our samples have no sulfides, and that it is positive. Hydrogen sulfide is a respiratory depressant.

DISSOLVED OXYGEN (mg/l or ppm)

Fonte dos Canos

Pias A-do-Pinto

Barragem do Enxoé

Poço dos Sopos

Tap water

January 2006

8 8 10 12 8 8

May

2006

6 8 6 6 8 8

Some second results were lower, may be due to temperature increased and higher pollution. Oxidability is not relevant to water human consumption, but very important for life in water.

COLIFORMS (not allowed in water for human

consumption)Poço de

PiasFonte da Figueira

Ribeira de Limas

Barragem do Enxoé

Poço dos Sopos

January

2006+ - + + -

May 2006 + +

Most water samples are contaminated with coliforms, a group of bacteria present in human waste, and most people drink this water without knowing that it is contaminated .

+ coliforms present / - coliforms absent

Conclusion

Water for human consumption should be tested before being drunk.