Analysis of Pesticides at Golf Courses using GC/MS

Significance of Topic

The quality of surface and groundwater on and around golf courses is closely linked to applied pesticides. Regulatory bodies have established guideline values and analytical requirements to protect public health and the environment. Simultaneous multi‐residue analysis by gas chromatography–mass spectrometry (GC/MS) provides a robust approach to monitor diverse pesticide classes efficiently and meet stringent control limits.

Objectives and Study Overview

This work evaluates three sample‐preparation and GC/MS methods for simultaneous determination of pesticides listed under Japanese Environmental Agency guidelines. Focus is placed on newly regulated compounds—acephate, metalaxyl, dithiopyr and pyributicarb—while maintaining compatibility with established targets. The study compares:

• Solid‐phase extraction (C18 + active carbon)
• Ethyl acetate extraction with salt‐induced partitioning
• On‐column injection for thermally labile analytes

Methodology and Instrumentation

Each 200 mL water sample was adjusted to neutral pH, spiked with internal standards, and subjected to one of the three extraction schemes. Extracts were dried under nitrogen, solvent‐exchanged to acetone, and concentrated to a defined volume for GC/MS analysis. A complementary HPLC‐based protocol addressed compounds unsuitable for GC.

Instrumentation

Shimadzu GCMS‐QP5050A system with DB-1 capillary column (30 m × 0.32 mm × 0.25 µm) was employed for GC/MS runs. Carrier gas helium, splitless injection, and a temperature program from 70 °C to 300 °C enabled separation of over 25 pesticide residues. On‐column injector at 70 °C was used for acephate and trichlorfon to prevent thermal degradation. HPLC‐UV and HPLC‐RF detectors were applied where indicated.

Key Results and Discussion

Method 1 achieved clear total ion chromatograms (TIC) for 28 analytes, with target quantitation down to 10 ppb in SIM mode. Newly added compounds exhibited characteristic mass fragments: metalaxyl (m/z 206), dithiopyr (m/z 354), and trichlopyr‐butoxyethyl (m/z 210). Method 2 delivered high‐sensitivity screening of herbicides including pyributicarb (SIM m/z 108/165) at 10 ppb. Method 3’s on‐column approach preserved labile phosphates (acephate, trichlorfon), though at higher quantitation limits (500 ppb) due to reduced sensitivity.

Benefits and Practical Applications

The outlined GC/MS protocols enable:

• Simultaneous analysis of multi‐class pesticides, reducing per‐sample time and resource use
• Compliance with regulatory guidelines for golf course water monitoring
• Adaptable workflows for compounds with varying thermal stability

Future Trends and Potential Applications

Advances such as high‐resolution mass spectrometry, automated SPE platforms, and data‐processing algorithms promise further sensitivity gains and broader analyte coverage. Integration with non‐target screening and real‐time field deployable systems may streamline routine environmental surveillance.

Conclusion

The three GC/MS‐based methods offer complementary strengths for comprehensive pesticide residue analysis in golf course waters. By tailoring extraction and injection conditions, both thermally stable and labile compounds can be quantified reliably. These strategies support regulatory compliance and environmental safety monitoring.