Off- specification in UVT parameters of Monoethylene glycol (MEG) sample

[Narahari]

This query pertaining to the Off- specification in UVT parameters of Monoethylene glycol (MEG) sample. If any body has experience in this area plz suggest..

I summarize little background of the matter as below,

- Vessel was carrying MEG cargo and at discharge port it was reported that the MEG wad Off- specification in UVT parameters at 220 nm, 250 nm, and at 275 nm. Sample was tested for full spec parameters to check the purity (MEG, DEG, TEG, Tetra EG content) by GC, and reported to be within specification limits. Also test on Iron content, water content, colour, chloride content, appearance was carried out and reported to be all within specification limits..

In order to check possible contamination with any volatile and semi-volatile organic chemical contamination (aromatics and polyaromatics) , we have conducted GCMS test and no any contaminations detected..

Now we are trying to find root cause for the possible contamination, that causes UVT off-specification. Any other procedure to identify this problem?

If any body has direct experience in similar situation, plz suggest in this regards. Thank you in advance..