<s>[INST] I recently found out that my son had mold in a classroom which is now explaining me picking him up 2-3 times a week with a headache and nausea . School never notified me and I took him to pediatrician with the symptoms that he had. Ran blood work and urinalysis . White blood cells were L 4.1 and Mono was high 13%. Pediatrician said he was just fighting something off could this be from the mold he was exposed to. School started in August and children were not removed from classroom until Nov or Dec and I didn t have test run until February because I thought his symptoms would diminish. They eventually did after children were moved out of classroom. [/INST] Hello and welcome To Chat Doctor forum. It is very difficult to pinpoint simple increase in monocytes to any particular disease without a detailed clinical examination. Headache and nausea can be because of anemia, malnutrition, infections and many other factors. Monocytosis or increase monocytes in the blood can be due to stress, viral fever, chronic bacterial or protozoal infections, malignancies etc. Most of the infection swill show a blood picture of increased Total Leukocyte counts. Some child Chat Doctor. I suggest a comprehensive allergy sensitivity testing which helps in finding out the relative sensitivity of a person to common molds, foods etc. Hope this helps, take care. </s>