I tried a sample .csv of only a few lines, and that worked. So then I split the data up into 2001.csv, 2002.csv, etc and found that I got the same error. because of this I simply shortened each year to 150 samples, and cleaned a few columns I didn't end up using, and this worked. Below is the final version of the code, thank you for all the help!
import arcpy
from arcpy.sa import *
arcpy.env.workspace = r"C:\Testing"
arcpy.env.overwriteOutput = True
in_csv_list = ["2001.csv", "2002.csv", "2003.csv", "2004.csv", "2005.csv", "2006.csv", "2007.csv", "2008.csv", "2009.csv", "2010.csv", "2011.csv"]
for in_csv in in_csv_list:
out_raster = in_csv.split(".")[0] + ".tif"
layer_name = r"C:\Testing\templayer"
x_field = "X"
y_field = "Y"
spatial_reference = arcpy.SpatialReference(4326)
arcpy.MakeXYEventLayer_management(in_csv, x_field, y_field, layer_name, spatial_reference)
cellsize = 0.08
value_field = "Total_PCB(ppm)"
assignment_type = "RANGE"
arcpy.PointToRaster_conversion(layer_name, value_field, out_raster, assignment_type, value_field, cellsize)
arcpy.Delete_management(layer_name)
del layer_name