Winter internship

The term environmental analysis means “Evaluation of the possible or probable effects of external forces and conditions on an organization's survival and growth strategies1”.

This training session will deal with the following parameters:

• Total Organic Carbon (TOC) in water , sediment & Biota.
• Polyaromatic Hydrocarbons (PAH) in water , sediment & Biota.
• Total Petroleum Hydrocarbons in water , sediment & Biota.

The participant will be expected to extract the analytical sample from the given matrix (sediment /water), apply sample concentration techniques and final use high end analysis instruments such as Gas Chromatography, or Gas chromatography coupled to Mass spectrometry to analyze the results.

The training session will take (5 days) to complete.

The TOC (Total Organic Carbon) is one of the most important composite parameters in the assessment of the organic pollution of water. Since it includes all carbon compounds as one mass, it is exactly defined and an absolute quantity. Therefore, it may be determined directly. In relation to the TOC also parameters like TC, TIC, DOC, (POC, VOC) are mentioned. The connections between these sum parameters and their meanings are shown in the following figure:

 

Pollution by organic compounds, many of which are known to be toxic or carcinogenic, has caused considerable and worldwide concern. Coastal and inland waters and sediment usually act as receptors for sewage effluents, industrial effluents and urban and rural run-off. As streams and rivers, lakes and ponds are frequently used for potable water supply, contamination of watercourses, where water re-use is practiced, is particularly undesirable. Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds which have received considerable attention because of the documented carcinogenicity in experimental animals of several of its members.

PAHs are fused compounds built on benzene rings. When a pair of carbon atoms is shared, then the two sharing aromatic rings is considered fused. The resulting structure is a molecule where all carbon and hydrogen atoms lie in one plane. The environmentally significant PAHs range between naphthalene (C10H8) and coronae (C24H12).

The term TPH (Total Petroleum Hydrocarbons) is a confusing one, and often misunderstood by the non-conversant as being a fixed definition of a petroleum product that can be measured absolutely, and hence be directly compared with other TPH values. Unfortunately this is not the case.

In short analysis of the total petroleum hydrocarbon (TPH) content of soil and water samples is complex and confusing.

Definition of TPH “Total petroleum hydrocarbon is the measure of the concentration or mass of petroleum hydrocarbon constituents present in a given amount of soil or water. The word "total" is a misnomer--few, if any, of the procedures for quantifying hydrocarbons can measure all of them in a given sample. Volatile ones are usually lost in the process and not quantified and non-petroleum hydrocarbons sometimes appear in the analysis3”.

The problem of TPH analysis stems from the complicated nature of petroleum products which can be complex mixtures of hundreds of hydrocarbon compounds, with the exact composition varying due to a number of factors including the crude oil source and the subsequent refining process. To complicate this even further are the changes to the refined product/spilled material caused by weathering once exposed to environmental conditions.

It is also worth noting that here are a number of other terms that are often used in conjunction with TPH:

• EPH = Extractable Petroleum Compound,
• DRO=Diesel Range Organics,
• GRO=Gasoline Range Organics
• EDRO=Extended Diesel Range Organics,
• SVOCs=Semi Volatile Organic Compounds with TPH being the sum of the aliphatic and aromatic compounds in the GRO and DRO and mineral ranges.

1. http://www.businessdictionary.com/definition/environmental-analysis.html#ixzz3E71H8Otk
   
2. http://www.lar.com/products/toc-analysis/toc-total-organic-carbon.html
   
3. http://www.caslab.com/Total_Petroleum_Hydrocarbons_TPH_Meaning​