Aquatic Pollution

Abstract

Aquatic pollution monitoring can help researchers envisage and study natural processes in the environment and determine human impacts on an ecosystem. These measurement efforts can also assist in restoration projects or ensure environmental standards are being met. The chapter describes very briefly the concept of dissolved oxygen, biochemical oxygen demand, fecal coli contamination, oil pollution, microplastic pollution in aquatic systems, trace metal contamination in the environment, and arsenic pollution in groundwater, etc. Moreover, it also depicts the measurement protocol for the above-mentioned aquatic pollution.

Appendices

Appendix 1

8.1.1 Preparation of Chemicals for BOD Test

Safety Note

At a minimum, hand, and eye protection should be used when handling any of the chemicals mentioned in this section. Before working with any chemical, consult the appropriate Material Safety Data Sheet (MSDS) to determine if other safety precautions are necessary.

8.1.2 Biochemical Oxygen demand Reagents

Phosphate Buffer Solution

Dissolve 8.5 g potassium dihydrogen phosphate (KH₂PO₄), 21.75 g dipotassium hydrogen phosphate (K₂HPO₄), 33.4 g disodium hydrogen phosphate heptahydrate (Na₂HPO₄ 7H₂O), and 1.7 g ammonium chloride (NH₄Cl) in about 500 mL of distilled water and dilute to 1 liter. The pH of this buffer should be 7.2 and should be checked with a pH meter. Discard this reagent if there is any sign of biological growth in the storage bottle.

Magnesium Sulfate Solution

Dissolve 22.5 g magnesium sulfate heptahydrate (MgSO₄ 7H₂O) in distilled water and dilute to 1 liter. Discard this reagent if there is any sign of biological growth in the storage bottle.

Calcium Chloride Solution

Dissolve 27.5 g anhydrous calcium chloride (CaCl₂) in distilled water and dilute to 1 liter. Discard this reagent if there is any sign of biological growth in the storage bottle.

Ferric Chloride Solution

Dissolve 0.25 g ferric chloride hexahydrate (FeCl₃ 6H₂O) in distilled water and dilute to 1 liter. Discard this reagent if there is any sign of biological growth in the storage bottle.

Sodium Hydroxide Solution, 1 N

Dissolve 40 g solid sodium hydroxide (NaOH) in approximately 800 mL of carbon dioxide (CO₂) free distilled water. Cool and dilute to 1 liter.

Safety Note

This reagent is corrosive and can burn hands and clothing. Rinse affected areas with large quantities of tap water to prevent injury and remove contaminated clothing, as residual may still damage the skin.

Sulfuric Acid Solution, 1 N

Cautiously add 28 mL of concentrated sulfuric acid (H₂SO₄), with mixing, to 800 mL of distilled water. Allow to cool and dilute to 1 liter.

Safety Note

This reagent is corrosive and can burn hands and clothing. Rinse affected areas with large quantities of tap water to prevent injury and remove contaminated clothing, as residual may still damage the skin.

Sodium Sulfite Solution, 0.0250 N

Dissolve 1.575 g anhydrous sodium sulfite (Na₂SO₃) in distilled water and dilute to 1 liter.

Note

This solution is not stable and must be prepared daily.

Potassium Iodide Solution, 10%

Dissolve 10 g potassium iodide (KI) in 100 mL of distilled water. Discard if the solution turns yellow.

The Acetic Acid Solution, 1 + 1

Carefully pour 50 mL of glacial acetic acid (CH₃COOH) into 50 mL of distilled water with mixing.

Safety Note

This reagent is corrosive and can burn hands and clothing. Rinse affected areas with large quantities of tap water to prevent injury and remove contaminated clothing, as residual may still damage the skin.

Sulfuric Acid Solution, 1 + 50

Cautiously add 5 mL of concentrated sulfuric acid (H₂SO₄) with mixing to 250 mL of distilled water.

Safety Note

This reagent is corrosive and can burn hands and clothing. Rinse affected areas with large quantities of tap water to prevent injury and remove contaminated clothing, as residual may still damage the skin.

Glucose-Glutamic Acid Solution

Dry reagent-grade glucose and reagent-grade glutamic acid at 103 °C for 1 h. Add 150 mg glucose and 150 mg glutamic acid to distilled water and dilute to 1 liter. Prepare this solution fresh immediately before use.

Nitrification Inhibitor

The Hach Chemical Company’s Nitrification inhibitor 2533 (2-chloro-6-(trichloromethyl) pyridine) or equivalent can be used for inhibition during carbonaceous BOD testing.

Appendix 2