[R] accessing variables inside a function, inside a loop

[Sacha Viquerat]

dear list!
I KNOW this has been answered a million times before. But, as some might 
remember from their "freelance" times as a statistic consultant, 
sometimes you're blinded by the facts. I KNOW I have seen this problem 
solved, but due to the mental blockade i have been suffering from the 
last 3 hours, I can neither find the answer on the mailing list nor on 
google. I wrote a function to plot one continuous variable against an 
abundance of fish, the data is called water. however, my data covers 9 
parameters, and since I am lazy as hell, I decided to write a for loop 
to pass all the variables to the function. as usual, the variables and 
the data frame cannot be found inside the function.

water<-read.csv("Henni/water-abundance2.csv",sep="\t",header=T)
source("functions.R")
attach(water)

names(water):
  [1] "site"     "sample"   "temp"     "pH"       "DO"       "BOD"
  [7] "COD"      "no3"      "no2"      "po4"      "N_male"   "N_female"

vars<-names(water)[3:10]

par(mfrow=c(4,2))
for (i in vars)
{
     comp.plot(i,N_male,DATA=water)
}

comp.plot<-function(parameter,y,DATA){ #this is actually in functions.R
     x<-DATA[[parameter]]
     y<-DATA[[y]]
     plot(y~parameter)
}

and of course, this doesn't work. I am really frustrated by now, since I 
have gathered all I could recollect from my past 2 years of R experience 
but still, I was not able to find a solution. I'm really dizzy right 
now, but since I will not be able to go to sleep unless I have found the 
answer to this problem, I urge someone to shed some light on my trivial 
problem! I will promise not to post this question ever again, but for 
now, I'm just stuck!

Thanks in advance and humble apologies to all that feel offended by my post!