Has anyone developed Toxaphen in water samples?

I typically do this was a pulsed splitless injection. 50 psi pulse for .5 min and purge flow to split vent of 50ml/min at .48 min. I typically use a single tapered direct connect liner in the GC inlet.

I have done it with both. 

Do you have any advice using EI? I have a customer trying to analyse toxaphene neat standards but for a high conc std (ppm), the sensitvity is very poor. They're using DB5-MS column, splitless, He carrier.