Update since starting zinc maintenance therapy

Hi there all, Sometime time back i wrote about my son Remo starting zinc therapy, commenced in January 2009 with zinc picolinate 150mgs daily, well tolerated, after about 6 weeks did 24hr urine test for zinc and copper, results were zinc output 6.05 milligrams/24hrs and copper output 64 micrograms/24 hours. Confirmed these results with Dr. Brewer, who said they were extremely good. All other tests being LFT, FBC and platelets, Iron Studies all good.
On the 1.6.09 did another 24hr urine test results came back that did not make any sense, for example Zinc 11,25 mg/24 and copper l53 micrograms/24hrs. I was quite disturbed at this because nothing had changed since the previous tests, the doctors here in South Africa are not that experienced in W.D. so not much help. I managed to telehone and speak with Dr. Brewer, he said that it could be a mistake that was done by the laboratories or non compliance, probably the former. He also mentioned that i could split the dose of zinc into 2 being morning and evening making it easier.
New tests done on 22.6.09 FBC and LFT within normal parameters, the iron studies are on the low side, this i am aware could be a side effect of the zinc.
24hr urine; Zinc 6.21 milligrams/24 and copper 59 micrograms/24 hrs. Acceptable good results. These results from a new laboratory.
New tests done 17.8.09 LFT, FBC all good, iron studies low. Copper 24 hr urine 50/24 hrs Still waiting for zinc results. I am now concerned that the copper results are low,indicating that perhaps overtreatment because of low values. I refer to Dr. Brewers book which i use religously, unfortunately the docs here have limited experience and i am on my own. I am considering lowering the dose of zinc to 100mgs daily and then see how he copes. Has anyone had a similar experience? I would really appreciate some comments.